Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: Nurse Julie on October 02, 2017, 05:15:41 PM

Title: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on October 02, 2017, 05:15:41 PM
LINK TO THE CB400/4 DETONATION THREAD
http://www.sohc.co.uk/index.php/topic,14609.msg122071/topicseen.html#new

OK, here goes

A bit of history. 1978 ‘T’ Honda CB400/4 F2.  Name ‘ Hettie’. Owned by myself  for just over 3 years and ridden regularly. Clock shows 46,838 miles, I don’t know if this is genuine mileage or not. It looks like the engine has been apart before sometime in its life. I have done about 4,400 miles on her since purchase. She has been regularly serviced at about 1000 mile intervals. She had a leaky oil pump which was due to brittle ‘O’ rings, so new rubber parts fitted. Sump gasket changed twice as I originally thought it was the gasket leaking. Had a problem with rising revs when the engine was hot which has been resolved by fitting non resisted spark plugs in place of the resisted plugs Dave Silver says are correct for this bike.

Last year she had a rattle develop somewhere in the engine, to me it sounded at the top end possibly on the left side. The rattle only lasted a few miles and then disappeared and did not return all last year. This year, half way through this summer, the rattle returned, intermittently, both under load and de accelerating. The rattle stopped if I kept her under about 5,000 rpm but still very intermittent as she would go for weeks without any undue noises. As I have plenty of other bikes to ride I took her off the road at this point.

She has always burnt a bit of oil and smokes a small amount under load but no more than any other old bike and I have oil vapour blowing back into the air box.
Everything else on the engine sounds fine, no knocking noises or clunking and the clutch and gearbox are great. She starts first time, every time. I do not pussy foot around on this bike. I ride her quite hard and she performs really well for a CB400/4.

So, now to the plan.

Engine out, strip and assess and rebuild replacing any parts that need to be and having any machine work done that is necessary. Engine casings will go for acid stripping and then she will be prepared and repainted using Triggers tried and tested methods.
At the same time, I will be having the clocks refurbished with new clock faces and I need to drop the forks out and give them a good looking at as they bottom out and get ‘stuck’ sometimes.
I am aiming to do the strip, assessment and rebuild of the engine myself and Trigger will do any machine work that is needed but, I would like to do as much of it as I possibly can.

Hettie is now on the ramp and I will start unbolting the exhaust, carbs and ancillaries tomorrow. I plan to remove the top end whilst the engine is still in the frame and then lift the engine out. I will post updates and pictures as I progress. I will not be offended if no one comments throughout the process as I know for many of you, engine strip and rebuilds are old hat but, for me it’s the first time for doing a 4 cylinder engine. I have taken the top ends off my old Brit bikes in the past but that is the extent of my engine experience.




[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on October 02, 2017, 05:30:51 PM
I will watch this with interest, i have never stripped one of these tiddlers so it's also a first for me, think it will be a few years before my 350/4 will get this treatment as she only has 5 and 1/2 k miles on her, as for the rattle my Z1000 has an intermittent rattle but i know what it is, end float on the cams quite a frequent problem on gs's as well, so plenty of pictures please.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 02, 2017, 05:35:08 PM
I shall enjoy this thread,

  always willing to learn from the experts
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on October 02, 2017, 05:40:26 PM
Good luck with the rebuild Julie. If you need a new cam or the rockers redressed I can recommend Newman Cams.
Don't touch the carbs!!!  :(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hondarc166 on October 02, 2017, 06:00:27 PM
I will watch with interests and learn more
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on October 02, 2017, 07:20:06 PM
Think we are all watching this one! No pressure then Julie.  :P Best of British  (or is that Japanese)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 02, 2017, 07:36:25 PM
Thanks Tim and everyone else............now, where is the BIG hammer  :o
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on October 02, 2017, 07:42:04 PM
 :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 02, 2017, 07:47:03 PM
Found this one!! Oops, 2 by the looks of it  ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 02, 2017, 07:52:05 PM
I hope you don't think it was me that made off with your sidepanel.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 02, 2017, 08:10:47 PM
I hope you don't think it was me that made off with your sidepanel.
No Mike, I know it wasn't you ( although I saw you eyeing it up). I have the panel off because I have nicked the battery temporarily for my CB550 project  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 02, 2017, 08:57:32 PM
Having just about finished my engine, I'll watch with great interest. They really are lovely little units - built like a Swiss watch.  Agreed, there are some bits which cause headaches but nothing compared with this single cylinder Norton which occupied my bench for far too long.  Still not quite finished but I'd had enough and wanted to do some interesting stuff. Don't know what you intend doing about the cam chain horseshoe but if it's buggered like most, I'll gladly make you a new pivot pin and dress the marks out - unless that's what Trig would do anyway.
I also strip the head and barrels off in the frame and build up the same way - it's much more manageable that way and everything added on is on a solid platform.

Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 02, 2017, 09:09:32 PM
Thanks Ian.
I had given thought to the horseshoe and luckily a very good original genuine one was available to me and another very kind forum member gave me some really good 2nd hand blades.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 02, 2017, 09:18:48 PM
Just a thought here, but everyone moans that Dave Silver recommends incorrect spark plugs. But, when these old Hondas were new, they had those dreadful metal shrouded plug caps, which to me suggest it was some kind of shielding for electrical interference. I've never tested the resistance of one of the original plug caps, but there is every possibility that they had far lower resistance than the NGK resistor caps that are available today, which would explain the recommendation of resistor plugs, but obviously with the modern caps there is an issue with resisted plugs as well. I know a couple of members have some of the old style shrouded caps, how about measuring the resistance of them? (Ash?)

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 02, 2017, 09:23:25 PM
Agree 100% with what your saying about the old metal caps  Hairy but Mr.DS advertises resisted plug caps and resisted plugs for the CB400/4.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 02, 2017, 09:59:18 PM
Maybe that's what NGK recommend, rightly or wrongly!

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 02, 2017, 10:41:07 PM
It affected the 405 line sets rather than the 625 line for technical reason which I've forgotten about.  Something to do with the way the luminance is modulated onto the carrier wave.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: AshimotoK0 on October 03, 2017, 12:31:10 AM
Metal shrouded caps are resistive ...  some are 5k Ohms , some are 10k Ohms.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 03, 2017, 08:03:39 AM
There's a four stroke scooter ( with Valentino Rossi paintwork) that passes our house each day and trashes the TV signal,  it's Freeview via an aerial.

Also the po-leece where above in a helicopter which blitzed the signal, presumably emergency rf channel transmitter.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on October 03, 2017, 08:42:04 AM
Oh dear Julie, it looks like your thread has been taken over by the resistance😊
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: AshimotoK0 on October 03, 2017, 08:43:40 AM
There's a four stroke scooter ( with Valentino Rossi paintwork) that passes our house each day and trashes the TV signal,  it's Freeview via an aerial.

Also the po-leece where above in a helicopter which blitzed the signal, presumably emergency rf channel transmitter.

I understand the original main aggressor was the Kawasaki H1, which in the late 60's, was the first Japanese bike to use CDi ignition as standard fitment. Lots of modern vehicles now use metal shrouded caps to reduce RFI. This is probably necessary in order to meet the stringent 'E' mark approvals for automotive electronics. I have got equipment through those approvals and I can tell you it's not fun and horrendously expensive.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 08:55:35 AM
Oh dear Julie, it looks like your thread has been taken over by the resistance😊
Very good Kevski  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 03, 2017, 09:35:19 AM
That is a good one kevski  :)

I do think there's more to the resistance in this motor though,  it'll be interesting to see inside it when you get it apart.
The resistance increase when it was running both plugs and caps with R shouldn't really have an affect at tickover. What it does is extend the spark duration from its initial start point. This in itself doesn't do much without something to burn,  so if youve got an old motor that's a bit windy and burning a little oil then you do have a source that is combustible and not controlled by the throttle slides.
That sort of mix is reluctant to fire but can be encouraged by a longer spark duration, which maybe what was happening inside this one.

It's an area they are having a punch up about in F1 as they are restricted in how much fuel they can use, but it looks as though they have been burning the oil as well. They even ran special oils in qualifying that people assume are orientated toward combustion which has been banned. They've now imposed maximum oil burn limits as well to try and prevent it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: MrDavo on October 03, 2017, 09:35:33 AM
To hijack a hijack.....

I seem to recall the metal shrouds were fitted as the GPO at the time complained if they weren't fitted they caused interference.

My CB750 from South Africa still had metal shrouds on the inside cylinders, though I replaced them in search of a misfire.

Before I got a ham radio licence I was into illegal sideband CB radio. I gave up doing it from home, after I got a visit from GPO inspectors, having been stupid enough to use the radio during Eastenders, wiping out the neighbours' TVs, so I went mobile, using a 100 watt setup from my car. I was talking to a mate as I drove down the full length of Deansgate in Manchester, looking in my mirror I saw to my horror lots of little flashing lights, as I had set off alarms all the way along the street!

Keep us posted on the rebuild Julie, has Graham sold you an engine stand yet?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 09:43:21 AM
To hijack a hijack.....

I seem to recall the metal shrouds were fitted as the GPO at the time complained if they weren't fitted they caused interference.


Keep us posted on the rebuild Julie, has Graham sold you an engine stand yet?
He has tried very hard to sell me one Dave but I'm too tight to buy one (typical CB400 owner !!!) This is going to have to be a quick strip/ rebuild as I'm incurring tool hire charges and workshop space charges 😭😭
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 03, 2017, 10:08:38 AM
That's bad Julie,
Tool hire and workshop space charges - Trig offered me overnight accommodation for next years C90 trip to Deutschland - unfortunately not passing your place - but he didn't mention CHARGES 🤓
Looking forward to seeing inside the motor,
Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: BigAl (Alan) on October 03, 2017, 10:29:31 AM
Very much looking forward to the engine work Julie,  gear boxes have always been some thing of a 'black art' to me.
Hijacked thread, as Ash mentioned the H1/H1A with CDI ignition was a big problem for Kawasaki in the USA 1968/69. I understand that the imported Euro versions thereafter where H1B with points ignition.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 03, 2017, 12:26:21 PM
That's bad Julie,
Tool hire and workshop space charges - Trig offered me overnight accommodation for next years C90 trip to Deutschland - unfortunately not passing your place - but he didn't mention CHARGES 🤓
Looking forward to seeing inside the motor,
Ian
He just sends the invoice later  ;D ;D ;)
Come on Julie the top end should be off by now.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 01:07:21 PM
That's bad Julie,
Tool hire and workshop space charges - Trig offered me overnight accommodation for next years C90 trip to Deutschland - unfortunately not passing your place - but he didn't mention CHARGES 🤓
Looking forward to seeing inside the motor,
Ian
He only charges me for workshop facilities Ian....no one else
Accommodation is FOC to everyone....including me  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 01:14:19 PM
That's bad Julie,
Tool hire and workshop space charges - Trig offered me overnight accommodation for next years C90 trip to Deutschland - unfortunately not passing your place - but he didn't mention CHARGES 🤓
Looking forward to seeing inside the motor,
Ian
He just sends the invoice later  ;D ;D ;)
Come on Julie the top end should be off by now.
The top end is almost off Paul. I have the rocker cover off, camshaft out and just started on the head bolts but I have got stuck on one of those nuts right down by the spark plug port, I just can't get it to move. I will have to wait for Trig to come back as I'm worried I will muller it, so need his input. I can't progress further with the head bolts as it says remove them in sequence....so I'm doing some ironing instead  :'( :'( :'( I will give a proper update later wish some pics. (On the engine that is, not the ironing  ;D ;D)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 03, 2017, 03:15:57 PM
No not that bothered about seeing you iron Triggers undies ;D ;D ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 05:40:03 PM
Drained oil, no metal debris on the magnetic sump bung. Removed all cables and ancillaries and got stripping.
You can see the oil jet tubes sitting behind the camshaft. 
[attachimg=1][attachimg=2]
Each is a different diameter and you can see the supporting grommet on the left one is broken.
[attachimg=3][attachimg=4]

When I unscrewed the hex bolts securing the cam chain tensioner holder, I was expecting it to spring up because that’s what it said in the book but there was no upward spring because the tensioner slipper was seized in the down position. I loosened off and fiddled with the tension adjuster at the bottom front of the cylinder block and hey presto, the slipper popped its head out of the tunnel.
The cam chain has a minute amount of movement on the cam sprocket but nowhere as much free play as I was expecting.
[attachimg=5]


Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 05:44:44 PM
Oil jets from the head.
[attachimg=1]

The head bolt on the left side down in the spark plug port was an absolute pain. I tried to undo it but could feel the socket slip off the nut. In the end I got Trigger to have a go and it took him over an hour of trying with all different tools, hitting, smacking, drilling and eventually it came off, in many parts. As a result I now need a new head stud. It was probably my fault in the first place as I didn’t clean all the old dirt out around the nut head and rounded it off a bit with the first turn of the socket !!.
So far I have found all genuine Honda gaskets and Honda pistons with original internal nuts and bolts so even though I said I think the engine has been apart before, Trig reckons it may not have been. Won’t know for sure until I get the cam chain off to see if it’s a soft link that someone has changed in the past to confirm if it has been apart or not.
I have left everything on the strip down bench for now but need to have a good clean up and inspection of the cam shaft / followers / valves / springs etc to see if there is any undue wear that needs attending to. There is nothing jumping out at present that looks bad or broken and it all looks in very good order to me, nice and clean and no rust.

[attachimg=2][attachimg=3][attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 05:47:25 PM
[attachimg=1]
The mullered head stud
[attachimg=2]


So, problems I encountered today.
I can never seem to lay my hands on the correct size spanner or socket, even though I seem to have hundreds out of the tool box !!
I do find it difficult undoing some of the very tight nuts and bolts, but managed them all except the one on the head which I needed help with.
I have to make my own cuppa's.....I always make him Tea when he's working !!
And.....the workshop now looks like a bomb has hit it and I have been told in no uncertain terms to clear it up.

Now, I have to think what I'm going to cook for dinner  :'( :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 03, 2017, 05:56:12 PM
That head stud looks like it's corroded in. 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 05:59:01 PM
That head stud looks like it's corroded in.
Yep, that's one of the next problems Mike, how to get the blighter out. I know Graham has these special stud removal thingies, so I will have a play.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 06:06:14 PM
A few more general pictures
[attachimg=1][attachimg=2][attachimg=3][attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 03, 2017, 06:19:55 PM
Looks like a really well cared for unit - the cam journals look like new and the cam will live to fight another day.  I usually dunk the piston crowns in cellulose thinners over night or even longer and the carbon just rubs off with a cloth, same with the valves when you do those.
I had a stud like that one a few years back and waited till the cases were separated and empty, then heated the general area (not too concentrated in one spot) and put the whole stud length in the vice lengthwise and screwed the case off the stud - there were 3 like that and all came away without damage (studs were knackered of course!)

Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: yozzer74 on October 03, 2017, 07:35:39 PM
Great job keep it coming  :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 03, 2017, 07:59:46 PM
And.....the workshop now looks like a bomb has hit it and I have been told in no uncertain terms to clear it up.
 ;D ;D ;D
Having seen his workshop I bet he has.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 08:19:42 PM
Seems to have been running rich, carbon should be a sort of biscuit brown BUT that was in the days of leaded petrol, might not be the same with unleaded.

I'd check the rings, there appears to be some blow past the rings as the piston skirts show burning. Area between top and middle ring has carbon on it, more than there should be and the gap appears quite large in the ring. I suspect it may need a new set of rings.

The cam followers look a little stepped, ask Graham to have a look at them as it might just be the light. Cam journals look really good, not a great deal wrong as yet.
Thanks Ken. There are no steps on the faces of the  followers, it's just the photo. I have seen steps on the engines Graham has in that big, it would be like jumping off a cliff for an Ant😁. Graham had said the rings had probably had it as the engine had too much crankcase pressure and oil and smoke in the airbox. I was going to fit new rings anyway but will see what the bores measure as may need a rebore and new rings.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 08:23:53 PM
And.....the workshop now looks like a bomb has hit it and I have been told in no uncertain terms to clear it up.
 ;D ;D ;D
Having seen his workshop I bet he has.
No Paul, I'm in the dirty workshop, not the inner sanctum of the engine building room !!. ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 03, 2017, 09:25:33 PM
And.....the workshop now looks like a bomb has hit it and I have been told in no uncertain terms to clear it up.
 ;D ;D ;D
Having seen his workshop I bet he has.
No Paul, I'm in the dirty workshop, not the inner sanctum of the engine building room !!. ;D ;D
is he being a bit petty then  ;) ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 09:31:49 PM
Ummmm, no, wouldn't call it petty and I did have lots of tools out of the boxes when really I only needed 3 different size spanners and sockets. Anyway, I had a tidy up in the workshop so he's happy again now. It's all ready for me to wreck again tomorrow  ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 03, 2017, 10:25:55 PM
Ummmm, no, wouldn't call it petty and I did have lots of tools out of the boxes when really I only needed 3 different size spanners and sockets. Anyway, I had a tidy up in the workshop so he's happy again now. It's all ready for me to wreck again tomorrow  ::) ::)
What is tomorrow's plan of action.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 03, 2017, 10:44:23 PM
Ummmm, no, wouldn't call it petty and I did have lots of tools out of the boxes when really I only needed 3 different size spanners and sockets. Anyway, I had a tidy up in the workshop so he's happy again now. It's all ready for me to wreck again tomorrow  ::) ::)
What is tomorrow's plan of action.
Shopping in the morning (food, not bike bits!!) and then I would like to do a leak down test on the head and strip the valves out and clean them up. I may have a go at refacing them if not bent, measure the valve guides and measure the bores and such like. I want to get all the top end cleaned and sorted before I delve into the bottom end.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 04, 2017, 07:46:09 AM
I've just done the engine in the 'other' 400 in completely the reverse direction to those I've done before.  Each part taken off was cleaned, assessed and either painted or plated and then stored.  When the final bit was reached on the strip down - the cases, once they were cleaned and painted everything was ready to build up.  It somehow seemed better than having a whole pile of manky bits and pieces cluttering up the workshop, dripping dirty oil all over.  My enthusiasm seemed to stay the whole course too.  The purists will probably cringe but I painted the bottom casing as well - much easier to keep clean.
Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 08:28:19 AM
I'm just doing it the way Trig does with all his engines. He has so many, for example, CB750 engines of customers in at the same time for rebuilds, it's like a military operation. Strip, assess, clean, acid dip cases, welding /machine work, paint cases. Every engine part is then moved to the engine building room and has it's own shelf on the racks. When he's got all the parts needed, which on some of these old engines could mean an awful lot of parts, everything is there, ready for the rebuild. So, if it works for him for all those engines, it should work for my one.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 06:09:06 PM
Well, things never go to plan, I haven’t got half as much done today as I had planned for one reason or another.

The leak down test was fine, no leaks from any valves.

I measured the bores, which are as follows :
        1                      2                    3                     4

   51.097             51.055              51.041           51.064

   51.036             51.084              51.025           51.039   

   51.020             51.072              51.011           51.022
     

The bores have no major vertical scuffs or scratches and look excellent to me but, at the top of 2,3 and 4 there is a little lip that I can feel with my fingers and about 10mm below the lip is a definite score going completely around the barrels that I can easily feel with my nails.
I spoke to Graham about this and asked would honing remove the lip and the score and he said it would remove the lip but if you tried to hone the scores out, you could be very near .25 over and then still no guarantee the score would be gone completely. He then went on to explain that he hones or re bores to the size of a physical piston + the relevant clearance, so was I going to buy a set of +.25 oversized pistons and rings, have a re bore and then find that the score is still there and then have another re bore to +. 50 and buy another set of pistons and rings?. As  have STD pistons fitted, it didn’t take much thinking about on my part as it makes sense to go with the +.50 pistons and rings, so that is what will be done.
The photos hopefully show the scoring. That’s it for a few days as have loads on until after the weekend, when I will strip the head completely.

[attachimg=1][attachimg=2][attachimg=3][attachimg=4]





Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Woodside on October 04, 2017, 07:14:59 PM
good to see even in  pro engine build workshop....the trusty quality street tin?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 04, 2017, 07:20:05 PM
As Trigger said Julie do it once. At least you have him to hand for good advice. ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 07:22:18 PM
good to see even in  pro engine build workshop....the trusty quality street tin?
Yes Jason, unfortunately no choccies left in the tin. That's in the 'dirty' workshop and is full of a load of rusty non Honda nuts, bolts, Allen screws etc that he finds when stripping engines. He wouldn't have a dirty old tin like that in the engine building room, that is cleaner than an operating theatre !!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 07:28:29 PM
As Trigger said Julie do it once. At least you have him to hand for good advice. ;)
Yes Paul, it is very handy being able to tap Trig for advice, he has his uses  ;D ;D ;D Joking aside, I don't know how anyone does this sort of engine work just by using a Haynes manual, it is so basic and it doesn't explain 'why' you need to do something a certain way, which is no good for an inquisitive girl like myself.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 04, 2017, 09:04:31 PM
Carefull you don't get the bug or you will be wanting your own workshop.
How is the 500/550 build going.
Can't remember which it was.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 09:28:50 PM
Carefull you don't get the bug or you will be wanting your own workshop.
How is the 500/550 build going.
Can't remember which it was.
My other bike is almost done now, it's a  CB550 mongrel. The tank and panels should be back from the painters next week. The downpipes are ready to bolt on along with a stubby silencer. Graham has fabricated a new clock bracket because I'm using lots of CB500 parts including CB500 clocks and because of the angle the cables come out of the clocks, they fouled on the headlight bowl. He has also fabricated a side mount number plate bracket. All the wiring is done and she fires. I now need to make the seat. I'm not planning to have it on the road until next spring. In the meantime I have parked her in Grahams office for the winter  ;D ;D[attachurl=1][attachimg=1][attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on October 04, 2017, 09:55:17 PM
I found a pair of Stilsons / pipe wrench is good for getting studs out of the cases. I bet Trigger has the stud detractors too, they work like the starter clutch with 3 rollers that tighten and grip the stud but I find whilst they are great for putting studs in they are not so good for stubborn extraction and slip and maul threads. Locking 2 nuts together against each other is probably more effective. I've had a few head nuts that have needed a lot of persuasion after buying a few very rough engines. A handy trick is to use a really cheap and nasty socket on the nut, then use a stick welder to stick the socket and nut together, rarely fails, another abusive method using 12 point sockets a bit too small and hammering them onto the rounded nut, Don't use triggers sockets like that, but those horrid cheap sets off the market are fine for that and if lucky they'll withstand a decade of that kind of use saving lots of aggro.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 04, 2017, 10:05:28 PM
I was tempted to use Stilsons and the woodwork chisels Matthew to remove that bloody nut !!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 05, 2017, 08:06:00 AM
Some of those bore marks look like water corrosion, bet the bike was not used for quite a while?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 05, 2017, 08:18:26 AM
You been using Triggers camera on those pictures of the bores  ;) ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 05, 2017, 08:20:13 AM
Some of those bore marks look like water corrosion, bet the bike was not used for quite a while?
Your right Bryan, the bike was off the road for at least 8 years according to PO. It may have been off the road at other times in it's life as well, who knows.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 05, 2017, 08:22:27 AM
You been using Triggers camera on those pictures of the bores  ;) ;)
No Paul, that was using my mobile phone camera which is what I have taken all these pics with. Just got too close I suppose. I will try harder next time  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 05, 2017, 12:22:42 PM
You been using Triggers camera on those pictures of the bores  ;) ;)
No Paul, that was using my mobile phone camera which is what I have taken all these pics with. Just got too close I suppose. I will try harder next time  ;D ;D ;D
Surprised Trigger hasn't mentioned it then after the stick you have given him :D ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 05, 2017, 01:33:03 PM
You been using Triggers camera on those pictures of the bores  ;) ;)
No Paul, that was using my mobile phone camera which is what I have taken all these pics with. Just got too close I suppose. I will try harder next time  ;D ;D ;D
Surprised Trigger hasn't mentioned it then after the stick you have given him :D ;)
Oh he's mentioned it Paul !!!!! ::) ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 05, 2017, 05:39:49 PM
You been using Triggers camera on those pictures of the bores  ;) ;)
No Paul, that was using my mobile phone camera which is what I have taken all these pics with. Just got too close I suppose. I will try harder next time  ;D ;D ;D
Surprised Trigger hasn't mentioned it then after the stick you have given him :D ;)
Oh he's mentioned it Paul !!!!! ::) ::) ::)
lol what goes around comes around😀😀😉
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 03:43:30 PM
Spent some time this morning stripping the head and cleaning and generally having a good inspection of the parts. The valves are all straight, very minor pitting so will just need re facing. Valve springs all OK and the observant ones of you will notice I have lost a washer in the process. It’s here somewhere !!!.
[attachimg=1]

Now, for those of you of a nervous disposition, you may want to sit down for the next bit.........

I cleaned the head fully and once all the old carbon and crud was off, look what I found !!!. No.s 1,2 and 3 totally bashed in. No.4 is ok. On the pistons the top rings are missing completely, there is a serious amount of damage to the top sides of the pistons and the edges of the top of the pistons look like the mice have been chewing at them. No.4 is fine, no damage whatsoever.

No 4 and 3
[attachimg=2]

No 2 and 1
[attachimg=3]

Pistons hanging off the head studs showing the damage to the tops
[attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 03:48:46 PM
And the damage to the rings / sides of pistons
[attachimg=1]
[attachimg=2]
[attachimg=3]
[attachimg=4]

The sump
[attachimg=5]

So, it seems that the intermittent rattle noise, once last year and twice this year was the rings breaking up and being bashed as the pistons came up and possibly bits of the rings going into the exhaust. This would tie in with me saying originally that the rattle was at the top left of the engine. Why it hasn’t damaged No 4, I don’t know. Also, at this stage I have no idea what caused this damage and if the damage has occurred whilst I have owned the bike or if it was already there to some extent and has just got a lot worse. I got Trigger to give the bores a thorough clean and a bit of a hone just to make sure there was no damage that I had not seen the other day and they are fine, no different than what I said last week.

We removed the engine from the frame today as well. Took the sump off, still no big bits of metal debris but when I ran my fingers over the bottom of the sump, it has a layer of very fine grey metal dust mixed with the oil, therefore…. grinding paste.

This means I now have to actually measure the cam shaft to see if it’s still within spec, as although it looks good, it may be beyond the service limit due to effect of grinding paste wear. It also makes me wonder what I am going to find in the bottom end of the engine, wear wise, for the same reason. I was going to split the cases today but need to digest and analyse the findings of this morning first I think.

So, questions I need to answer are, 1) What caused this damage, where should I start looking for the cause?. 2) Has all this damage occurred in my ownership (just under 5,000 miles) or is it old damage that has progressively got worse?. 3) Why is No.4 not showing any signs of damage?.

What I have learnt this morning is that when Trigger says you can never really know what you’re looking at until every single part of an engine is fully stripped and fully cleaned, how right he is !!!

Trigger is not concerned about the damage, he says it is all repairable but to me it looks bloody awful and I am really quite concerned about it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on October 09, 2017, 03:53:52 PM
Ouch - like cheeeesse Gromit! Hope no more nasties further on.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 09, 2017, 04:28:25 PM
Ooh, that looks soooo expensive! I think you can discount ignition system fault, as you would have damage to number 4 as well as number 2. Possibly a weak mixture on 3 cyls, number 4 running richer than the others possibly. The worrying thing is that it only had a minor rattle as you described it. Some I've heard out on the road positively knock pop and bang, what the hell must they be like inside???? I'd love to be able to blame a female rider for causing the damage, but really can't say for sure! It might be worth sending the pistons to Ash or one of the metallurgy guys on here to see if they have any idea, possibly even a duff batch of pistons, although I very much doubt that of Honda. One more thing that springs to mind is the fact that 400/4s carbs have a fast idle when the choke is on, and remembering what Bryan J said about some Honda twins destroying pistons/rings if revved before warming up properly, maybe that has happened here, but why not number 4????? So my first idea seems most likely to me, weak mixture. :o :o
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 04:38:17 PM
I will let you blame it on a female rider Hairy, only because it's you though and I wouldn't expect anything different from you  :-* :-*
It really was only a very minor rattle but I'm pleased I took it off the road when I did, I dread to think what would have happened if I had just ignored it and kept riding her !!! Graham has also mentioned what you said in your last point, hard riding on a cold engine. I don't always warm her up fully but I never thrash her when she's cold, only when hot, and like you say, it doesn't explain why No.4 is still OK. It's amazing seeing the damage as the bike was running and performing very, very well. If it hadn't have been for the rattle, I wouldn't have even considered taking her off the road, let alone taking the engine apart
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 09, 2017, 04:50:27 PM
That looks like classic detonation,  always the rings get blamed as it ultimately takes them apart in the end but it starts with combustion conditions,  most likely as hairy says,  too lean,  and if ignored will get to the rings by melting the edge of the pistons.

I bet if you took those parts to the airfield near you with the old planes flying over you,  then those engine guys will give you a guide as to what went on.
Don't know if you looked in on the twin cylinder head thread recently as it's very similar to that one.

Does look a bit scary though.

Probably the source of extra air when you were struggling with tickover.

Nigel.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 09, 2017, 04:52:09 PM
Oddly enough, when I bought my only brand new Honda, a CB125T2 back in 1981, the fitter said to me, always let it idle or as close as you can until the rocker cover is too hot to keep your hand on, then ride it, and that way it should last for ages. I've always done that with all the other Hondas I've ever owned, and never had a piston or rings give out on one. So worth bearing in mind once it's back together!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 05:02:15 PM
Thanks for your input chaps, I really do appreciate it very much. I will add here that Trigger is saying exactly the same things and I believe him 100% but it's just nice to hear the same things from other such knowledgeable people who have had hands on practical experience of these things.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Seabeowner on October 09, 2017, 05:07:07 PM
Amazing amount of damage for an engine that still ran reasonably well and the top end looked so clean. Presumably its had a few oil changes in the 500 miles and something would have shown. Are you sure the rattling noise was not detonation? Sure sign if opened throttle up from fairly low revs under heavy acceleration.
I'd put those pistons up somewhere as trophies.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 05:17:39 PM
Oil changed every 1000 miles and she was performing fantastically. Are you calling 'detonation' noise what I call 'pinking' if so, definitely none of that.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 09, 2017, 05:32:12 PM
It could be that the previous owner had run it weak (pod filters and or non standard pipe?)  Probably couldn't get it to run right and went back to stock, but the damage was already done. The carbon on the pistons and head hid the damage initially until you got the barrels off and started cleaning bits up. That's why I cringe when people on here  ask about pod filters on cafe racers, I always advise against it, and kinda look forward to the inevitable posting of pictures like yours, while thinking to myself "told you so" Obviously once damage of that nature has occurred, even running properly it will only get worse, as you have sadly found. I worked on many two strokes with pods over the years, usually with a hole the size of a 10p piece dead centre of the pistons, they are totally bad news.

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 09, 2017, 05:41:26 PM
I was just thinking the same as you hairy,  the amount of carbon visible in the number 1 piston looks like it happened some time ago. Don't know if it's fallen out of the others as you've cleaned them. Seems to have done a decent job of holding compression up though,  guess it's a bespoke shape to fit it  :)

I'd guess at it happening some time ago. Detonation (yep,  pinking)  that sounds like if you dropped a M8 nut into a porcelain hand basin from about three feet up so it rattled around. Likely this was previous owner.

Hairy,  it understand that piston centre melted is not detonation but pre-ignition that gets the centre of the piston bouncing up and down like a trampoline as it gets hot enough to melt through like you've attacked it with a cutting torch.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 05:49:22 PM
Haha, yes, I remember 'pinking' very well, I had a Vauxhall Chevette that did it in every gear under load !!!. What my concern is I suppose, is if it were something I have caused, how can I rectify it to make sure it doesn't happen again? Now, if it was the PO that had it set up wrong thus causing the damage and then me just being the one owning it when it presented it's problems, then I can't change anything to prevent a further failure.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 09, 2017, 06:21:32 PM
I messed that up,  I should have said dropped from a metre as I was working in metric with an M8  :D

You may have just invented carbon piston rings,  could call them graphene in a honed fossilised matrix and claim design rights.

Those Chevettes where quite a nifty chassis with double wishbone front suspension and panhard rod location for a coil spring axle at the rear. Escort owners would kill for something so good,  they're still welding bits on them nowadays to get them that good.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 06:28:07 PM
The engine blew up on my Chevette going up the old A21 at Polhill in 1982. Got my Dad to come and pick me up, left the car and never, ever went back for it. Could still be there in the undergrowth for all I know but, doubt it  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 09, 2017, 06:57:42 PM
Mind boggling how that was still running  :o :o :o
Good luck with the rest of it Julie in at the deep end with this one ;) ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 07:02:05 PM
Mind boggling how that was still running  :o :o :o
Good luck with the rest of it Julie in at the deep end with this one ;) ;D
Just my luck Paul. I thought a new set of rings, new cam and primary chains and a cam chain horseshoe would do the job a treat.....never mind, keeps the old grey matter active  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on October 09, 2017, 07:03:48 PM
Mind boggling how that was still running  :o :o :o
Good luck with the rest of it Julie in at the deep end with this one ;) ;D
Julie, if its any comfort - mine WAS running rough when you saw it at the Crich do - what will that look like?? Watch this space :P
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 09, 2017, 07:05:43 PM
Look on the bright side, if you crack this one then any other should be a doddle.
Ask Graham if that is the worst piston damage he has seen on a decently running engine.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 07:07:25 PM
Mind boggling how that was still running  :o :o :o
Good luck with the rest of it Julie in at the deep end with this one ;) ;D
Julie, if its any comfort - mine WAS running rough when you saw it at the Crich do - what will that look like?? Watch this space :P
I think every 400/4 owner on here should strip their engine at the same time as me Tim, hopefully someone has worse problems than me  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 07:09:32 PM
Look on the bright side, if you crack this one then any other should be a doddle.
Ask Graham if that is the worst piston damage he has seen on a decently running engine.
Graham says No, he says he has seen alot worse than that!!!. Hettie's engine was running perfectly even with the pistons in that state. She also only burnt about 100-200 mls of oil every 1000 miles. She was a flying machine.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 09, 2017, 07:29:06 PM
yes,she did run well,

 my 500 had that issue about 5 years ago, 1 piston was damaged and top ring vanished ,2 piston just had cracked top ring and no damage,3 and 4 were ok.

 new piston and 4 sets of rings sorted it,

  luckily no damage to the bores,

  used a demel to smoth out the head,

 the reason given by others more expert than me,was revving to hard when cold

hopefully the filter will have trapped the small debris ,as you say,the cam looks ok



 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 07:54:49 PM
yes,she did run well,
Yes John but I couldn't keep up with you  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Trigger on October 09, 2017, 07:56:42 PM
The damage is very old, down too much air either from a pervious air leak or not been set up right. The problem is the damage is too old and maybe the cause will never be found. It is unbelievable as this engine started first time every time and not even bad compression. It is still strange that number 4 is perfect. Julie has forgot to mention how many times it has been taken through the red line, when her head is in race mode ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 09, 2017, 07:57:26 PM
yes,she did run well,
Yes John but I couldn't keep up with you  ;D ;D

  well,mine has 65000 on the clock,nicely run in,so spins over well !!!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 08:07:20 PM
yes,she did run well,
Yes John but I couldn't keep up with you  ;D ;D

  well,mine has 65000 on the clock,nicely run in,so spins over well !!!!
So with mine at 47000 miles, do you think I should put my pistons back in for another 1000 miles and see if they bed in any better  ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 09, 2017, 08:08:54 PM
yes,she did run well,
Yes John but I couldn't keep up with you  ;D ;D

  well,mine has 65000 on the clock,nicely run in,so spins over well !!!!
So with mine at 47000 miles, do you think I should put my pistons back in for another 1000 miles and see if they bed in any better  ;D ;D ;D ;D ;D
Might need new rings

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on October 09, 2017, 08:30:00 PM
How long have I been away 7 pages in to your rebuild already.
When your finished fancy having a go at mine  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 08:38:19 PM
How long have I been away 7 pages in to your rebuild already.
When your finished fancy having a go at mine  ;)
Thanks for the offer Mick but.......NO  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on October 09, 2017, 08:46:27 PM
Are you sure I have 2 well uncared for engines with no history and both have stood since 1990.
You should have them done in a week or two  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 08:50:41 PM
Are you sure I have 2 well uncared for engines with no history and both have stood since 1990.
You should have them done in a week or two  ;D
Send them up to Trig , with a blank cheque and he will have a look. You may need to find a part time job though to pay the final bill !!! ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Woodside on October 09, 2017, 08:59:32 PM
this thread is gonna break all uk records
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on October 09, 2017, 09:00:54 PM
I don't know about a blank cheque I can send a blank stare  ;D ;D
Time for a part time job would be nice. I fell asleep in the van at lunch time today and woke up with the customer standing next to me about an hour later  :-[
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 09, 2017, 09:05:02 PM
this thread is gonna break all uk records
You could be right there Jason but, it was never going to be straightforward with a Woman involved in it  ::) ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on October 09, 2017, 10:24:10 PM
My first 550 was like that, on all pots. Still ran ok but had previously been rebuilt with lots of gasket goo and old gaskets 're used. Leaked like a sieve and didn't like to start if hot, but still get to an indicated 105 mph in that state. The bottom end was fine, must have done 10k miles without any missed gears etc. The head proved ok too and was put back in service.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 10, 2017, 07:43:58 AM
Used to see that sort of damage regularly on CB175 and the K3/4 250's if the engine was "thrashed" from cold, nearest explanation i got was from a man called Stan Dibbden who was the NGK rep and used to race sidecars a loooong time ago, he reconed that it was differential expansion when haeted too quick nipping the rings and shattering them. These broken bits then worked there way out of the grooves and got hammered into the head.

As to how good he was I was servicing a two stroke 250, cant remember Suzuki or Yamaha but he picked up the plugs and examined them with an eye glass and told me to take the heads off as a piston was about to hole, he was right! and the plugs looked a good colour as well
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 08:26:53 AM
I had to look again at the first set of pics you posted with the pistons. Now you look closely you can see the damage on the crown and the one pic you showed of the side where I commented that it was showing signs of compression loss past the rings as the skirt was burnt is No4 piston. I'm wondering though how you missed the gaping holes in the rest of them Julie, no amount of carbon would hide those holes. I've seen worse but not for many many years, damn that's a mess.
I missed the damage Ken because I wasn't looking for it at that stage. I was concentrating on the head that day and I think the pic I put on of the top of the pistons was just a random photo showing the carbon build up. It wasn't until i took the pistons out yesterday and started cleaning them up to have a closer look that i found the damage. The holes on the pistons were full of carbon and melted piston rings.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 10, 2017, 08:50:33 AM
I believe the two stroke melted piston problem is pre-ignition which is usually,  as you say Bryan, related to the plugs. It's normally the plug getting too hot which is what the NGK guy was looking for and it's different to mixture. With a magnifying glass you can see if you have got any electrode melt on the plug, this shows the plug is too low a heat range ( low number in NGK) but the mixture and colour can be correct.

With road going two stroke it's plug fowling that you're trying to avoid to make them run reliably,  so you use a plug that's going to run hotter than a race motor. The risk is if you get alot of flat out running then the plug tip overheats and starts to glow red,  it's this that sets off the new mixture well before the desired timing event "pre-ignition" and causes such catastrophic heat build in the piston crown.
It's usually the opposite in a two stroke race motor. They use a plug higher up the NGK heat range which will withstand the flat out combustion heat during a race,  but of course you get that classic racer's problem of fouled plugs as they won't self clean when run at less demanding speeds.

Just broken rings in an engine leaves a characteristic imprint in the head of very sharp and defined marks,  these examples have very clear aluminium melt than only comes from detonation. As opposed to pre-ignition, this follows the start of the engine spark being timed and they are very different causes.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: MrDavo on October 10, 2017, 09:48:28 AM
It shows what tough little buggers these engines are that it could bob along quite happily in the state, albeit with a slight rattle.

Way back when we first saw the bores there seemed to be signs of water damage, I was wondering if this is one of those engines that has seized over time as the rings have rusted into the bores. Along comes Bubba with his trusty breaker bar, and without pausing to wonder why it's called that, manages to free the engine and get it running, quickly flogging it on. What he couldn't see was the carnage caused to the stuck rings, ripping them out of their lands, and the debris damaging the head before eventually exiting through the exhaust port.

It could even explain the mystery of why #4 pot is ok, if that cylinder was lucky enough to be on compression, with both valves shut during the long stand.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 10, 2017, 10:21:41 AM
I think that's an entirely plausible route to damage an engine and really don't think any theory should be discontinued when looking at this type of subject.
 
But, I would offer to counter that in the melted parts of the alloy it shows very high heat was present. If you just physically break the rings and piston lands you just don't get melting. The little craters, like moon examples, show straight up detonation of uncontrolled fuel burn and you can see the piston structure melted and smeared both up and down around that top ring area.
It's interesting that a few of these are appearing on here with this one,  matt mouse, John webbley,  the twin cylinder heads on another thread all showing what seems to be the same. We've not got pictures from some of those mentioned though.
One of the main influencers of detonation is fuel octane performance. We don't usually have anything below 95 oct now,  I think. But these bikes cover the period of two star which was 92oct with the attendant risk going up for that fuel in these engines.
Picking up on trigger saying this happened a long time ago,  I'd hold with that too judging by how much carbon was it the ring spaces. It could even have happened in the 1980s.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: MrDavo on October 10, 2017, 10:57:19 AM
Could little broken bits of ring be tempoaraily embedded and glowing brightly, causing melting? Some of the head damage looks to me like physical impact rather than heat, but I agree about the piston craters looking like they were caised by melting

It would logically be harder for the heat to soak away from the piston crowns than for the head, plus its going to get hotter with blowby caused by the missing top ring heating the piston rather than leaving through the exhaust. Normally, heat applied by normal running to the piston crown would dissapate through the top ring to the cylinder bore, without that there, where would it go? Would it build up until things got so hot the piston top began to melt? It doesnt do so catastrophically because there is still a path for the heat through the surviving ring and can soak into the piston and wristpin / conrod, but could cause the damage we can see.

I agree there seems a lot of commonality with the damaged twin head we saw the other week.

What makes me dubious about the low octane or bad timing explanation is why would #4 not be just as bad?
I'm not trying to start an argument, just to make sense of a mystery.  8)

ETA: Mine was running hot on one pot due to a rock hard inlet rubber that wouldn't seal properly, I guess if number 4 sealed Ok and the rest didn't, then that would do it just with heat. Were the pipes blued?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 10, 2017, 02:27:40 PM
MrDavo,  I've no problems with opposing views. I feel that anything I write on here should be up for scrutiny,  if it won't stand up to your enquiring mind or any others with experience in different areas to me then it can't be seen as truly valid.

Slightly wary about trampling over Julie's thread as it originally started but I guess the subject is relevant as the motor looks such a mess. For anyone coming to this thread later on if they find themselves with something similar,  then it's thoroughness will be of interest. It's something that I think is worthwhile in that it should shake out the real problem,  threads on other forum when it starts well but never really concludes what went wrong I find frustrating. Especially if I'm looking to gain from that problem and how those poster's split it down to find what failed and how.

Your observations about air leaks are entirely valid as well,  guess that's why everyone on here all shouts "airleak" when a new poster comes on with a running inconsistency,  they can be so minor and frustrating or really significant.

I'll post on what I understand how detonation happens to see if that adds to the overall view.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 03:19:36 PM
Were the pipes blued?

No they weren't into porn, these were good little pipes as befitting a ladies bike.
No blued pipes chaps, double skinned original Honda downpipes fitted.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 04:34:20 PM
Positive steps forward today. Split the crank cases and no damage evident at this stage. All cogs have their teeth, the gearbox looks good, measured the dogs and they are well within spec at 5.79-5.91mm with a service limit of 5.5mm.

[attachimg=1][attachimg=2]

The cam chain tensioner horseshoe is in one piece although the pivot pin was a little tight. The cam chain is the original. The primary chain is the original and is knackered.

[attachimg=3][attachimg=4]

Have taken all the bearings out of the cases and off of the con rods. These actually look in really good condition considering the amount of swarf that could have been going around the engine but, won’t know for sure until measured.
I have cleaned all the parts and have been given a corner of a shelf in the Engine building room to start storing everything when it's cleaned until the engine is ready to be rebuilt.

[attachimg=5]

Graham has another slot booked at the acid dippers in about 3 weeks time, so I have put all the casings etc in a crate and they can go in with his next lot of engines that need the acid treatment.

The measuring of the shells will happen when I get the cases back so they are all nice and clean to work with, but I’m sure there can be some bits I can measure in the meantime, like the camshaft. Also all the machine work will be done after acid stripping. I can also start cleaning the nuts and bolts prior to sending for zinc plating. The outer casings had a lot of Allen bolts fitted but I am going to go back to what was fitted as standard.

What I have learnt today, 1) My cleaning of parts standards fall well short of Triggers exacting requirements. I would wash a load of bits in the parts wash and put them on the drying racks and he would look at them and give them back to me to do again, some parts came back twice !!! >:( >:( But, I suppose that is one of the reasons why his engine building is so excellent. 2) Don't turn gear shafts with cogs, bearings, circlips, spacers etc on their ends in the parts wash, all the cogs etc fall off and I have no idea where they came from or in what order. Trig made me get the workshop manual out and work out where all these bits belong and made me re assemble them  ::) ::). 3)Don't get the cleaning solution from the parts wash all over the floor when transferring the parts to the drying racks. It was like an ice rink and I had to scrub that part of the workshop floor :'( :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on October 10, 2017, 04:39:50 PM
What I have learnt today, 1) My cleaning of parts standards fall well short of Triggers exacting requirements. I would wash a load of bits in the parts wash and put them on the drying racks and he would look at them and give them back to me to do again, some parts came back twice !!! >:( >:( But, I suppose that is one of the reasons why his engine building is so excellent. 2) Don't turn gear shafts with cogs, bearings, circlips, spacers etc on their ends in the parts wash, all the cogs etc fall off and I have no idea where they came from or in what order. Trig made me get the workshop manual out and work out where all these bits belong and made me re assemble them  ::) ::). 3)Don't get the cleaning solution from the parts wash all over the floor when transferring the parts to the drying racks. It was like an ice rink and I had to scrub that part of the workshop floor :'( :'(

God he sounds worse than my old english teacher  ;D ;D ;D ;D ;)
Glad the rest of it looks OK
If you are going to learn then learn from the best ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 10, 2017, 05:30:43 PM
I think oil filters are about 10 to 15 micron filtration so not much in the way of bits will go through them.

Different for the oil pump though as it's only got a sieve to stop the chunky bits getting in there.

Most of the rings usually go out the exhaust valve and don't generally go down past the piston if it remains intact so the rest of the engine doesn't see much of the broken parts.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 06:39:31 PM
Mr Davo, Oddjob, Hairy, K2-6, Bryan and everyone else who have given their theories' and insights, I think your input is invaluable to this thread and please do carry on. This is a huge learning curve for me but maybe also of interest to other current members of this forum and future members' also. It would have been alot easier me doing this in 'private' ie, not sharing with anyone else but, what's the point in that......no one learns by my mistakes or enhances their knowledge base by something I get right. I still think the diagnostics are the most important part of this process as a means of hopefully preventing it in the future.
Thanks all for your interest.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on October 10, 2017, 08:14:58 PM
I'm very much inclined to think the rings gaining a bit of rust in a prolonged lay up theory is why the rings would break up like that. On my 550 it had a indicated milsge that was not that high, - I cannot remember the figures exactly but around 30k, I doubt that bike had been around the clock given the wear elsewhere on it, but it had doubtless been stood a long while given the rust that had been painted over.
I suspect the rising values of Sohc bikes will see more bikes dragged out, forced to turn over then thrashed and flogged quick so if the theory is right we can look foreward to more of these threads. I've seen a few pistons where the rings have picked up on the cylinder, they do melt rather readily. I've also had a few where the piston have pre ignited and holed the piston, to me this looks like the damage from the bits chewing the head up. - the melting to me is as likely to be friction from repeatedly hammering those bits of ring til they exit and running temperatures combined. I did blacksmithing in collage and it was a trick of the old hands to take a bit of cold 10mm diameter steel, and hammer it so fast they could light a cigarette  off it, so I reacon the melting might just be that. Rings are really brittle and easy to shatter so I can well imagine a bit of rust in the bores causing them to fail. Worst case of this kind of abuse I've seen was a dumper engine I bought a few years ago, probably easy start causing the top of the piston to fail ( they have a small pocket in the top of the piston with a spike inside it and a washer fixed around that to aid cold starting ) the washer had come loose off the piston, similar damage to the head  to look at although the rings survived ok I think. It had obviously been run that way for a long, long time as the valves were bent and stuck plus the exhaust port was almost closed up with soot, crank though free turning was down to copper on the main and big end bearings. Con rod was a bit bent too. Just the impact seemed to leave the head and piston crown in that condition.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Craig CB400 on October 10, 2017, 08:40:44 PM
If it makes you feel any better Julie my 45k restoration project was equally mullered when I stripped it down and funnily enough mine also had 3 pistons and crowns damaged.

(http://i346.photobucket.com/albums/p436/craig301/20160820_143320_zpsnmezht3y.jpg) (http://s346.photobucket.com/user/craig301/media/20160820_143320_zpsnmezht3y.jpg.html)

(http://i346.photobucket.com/albums/p436/craig301/20161014_163933_zpskzhbxios.jpg) (http://s346.photobucket.com/user/craig301/media/20161014_163933_zpskzhbxios.jpg.html)

(http://i346.photobucket.com/albums/p436/craig301/20161014_163949_zpsbczassuv.jpg) (http://s346.photobucket.com/user/craig301/media/20161014_163949_zpsbczassuv.jpg.html)

Mine had sat since 1997 and wasn't run for 9 years, promptly broke and sat for another 9 years before I bought it, just proves these things need to be ridden to be in good shape
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 08:47:46 PM
That's really interesting Craig, also good to see another wrecked engine  ;D Can you remember if #4 piston was ok or was it one of the others?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on October 10, 2017, 09:05:26 PM
Craig, you are right, these bikes are far better off being used, my cb500 got to 250,000 miles and the engines in better  shape, just needs new rings and one selector fork plus gear it runs in.
Julie, you need to see the contents of my shed - plenty of wrecked engines in there, thanks to my buying at the very bottom of the market.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Craig CB400 on October 10, 2017, 09:15:29 PM
That's really interesting Craig, also good to see another wrecked engine  ;D Can you remember if #4 piston was ok or was it one of the others?

It was an end one on mine too, also had the same damage to the rings and sides of the pistons. My research on the cause was not definitive but best guess was the carbs running very lean and judging by the state of them when I checked them it may be right

(http://i346.photobucket.com/albums/p436/craig301/ba8dcab5-ef5a-4934-9fe7-e181dd61a2d2_zpsoyaphp6s.jpg) (http://s346.photobucket.com/user/craig301/media/ba8dcab5-ef5a-4934-9fe7-e181dd61a2d2_zpsoyaphp6s.jpg.html)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 09:23:19 PM
Craig, you are right, these bikes are far better off being used, my cb500 got to 250,000 miles and the engines in better  shape, just needs new rings and one selector fork plus gear it runs in.
Julie, you need to see the contents of my shed - plenty of wrecked engines in there, thanks to my buying at the very bottom of the market.
I would love to look in your shed Matt ;D. I think the consensus from the experts on here is that this damage had occurred prior to me owning the bike and yes, it was definitely off the road for 9 years before I got her. So this brings up another learning point which is that if a bike has been sitting for however long not being ridden, it may be years (nearly 4 in my case) and miles (almost 5000 in my case) before a pre existing problem worsens and presents itself. I am now beginning to understand why with every bike that Trigger buys, (and i mean every bike !!!) regardless of condition or if the PO says it has had an engine rebuild or the bike has undergone restoration, he strips that bike right down to the frame, including the engine because he wants to check every part for himself, just to make sure it's ok.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 10, 2017, 09:39:10 PM
That's really interesting Craig, also good to see another wrecked engine  ;D Can you remember if #4 piston was ok or was it one of the others?

It was an end one on mine too, also had the same damage to the rings and sides of the pistons. My research on the cause was not definitive but best guess was the carbs running very lean and judging by the state of them when I checked them it may be right

(http://i346.photobucket.com/albums/p436/craig301/ba8dcab5-ef5a-4934-9fe7-e181dd61a2d2_zpsoyaphp6s.jpg) (http://s346.photobucket.com/user/craig301/media/ba8dcab5-ef5a-4934-9fe7-e181dd61a2d2_zpsoyaphp6s.jpg.html)

A matching set Craig !!!
[attachimg=1]

And the back side
[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Trigger on October 10, 2017, 09:45:17 PM
Did you mention chains Oddjob  ;D I empty this bloody box every six months, get through a few  ;)

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 11, 2017, 06:06:47 AM
That grey sludge in the bottom was probably not grinding type paste but well chewed up bits of alloy from anywhere, those chains and gears mush alloy up really well, ask Trigger about the 175 and 250 centrifugal oil filters! On looking the shells I would use again as long as you know which rod/hole they came from, same with horseshoe, looks in really good knick---just make sure it pivots extremely freely and locktite the two special retaining bolts in---I have seen those come loose. New tensioner springs would be nice but I don't think they exist any more, sure a similar size but maybe a bit stronger can be found
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 08:45:31 AM
That grey sludge in the bottom was probably not grinding type paste but well chewed up bits of alloy from anywhere, those chains and gears mush alloy up really well, ask Trigger about the 175 and 250 centrifugal oil filters! On looking the shells I would use again as long as you know which rod/hole they came from
Yes Bryan, I marked all the shells, valves, rockers etc on taking them out so I know where they belong.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: JamesH on October 11, 2017, 09:01:37 AM
Just catching up on this thread Julie. Holy sh*te, you've been busy !!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 09:05:40 AM
Just catching up on this thread Julie. Holy sh*te, you've been busy !!!
Yes James, I'm a woman on a mission  ;D ;D Also, I have been given a certain amount of time in the workshop, if I go over that time I incur penalty charges  ::) ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: JamesH on October 11, 2017, 09:08:15 AM
Jesus my penalty charges must be running into the thousands by now then
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 09:10:08 AM
 ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 11, 2017, 03:40:05 PM
I think the original question you posed somewhere near the beginning of this thread Julie about "how do people know what to do just from manuals" is answered after what you take on with something like this.

After training in this sphere as a few on here have done,  much of the experience then is added as they take on work that had variously involved failure,  mistreatment and any number of ways that owners have generally cocked up what started out as a well running bike.

A vocational degree course in failure. Workshops are never surprised at what lengths people go to in mucking things up. You've almost written a Haynes manual yourself on here regarding these engines,  probably two thirds still to go.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on October 11, 2017, 04:10:05 PM
Just catching up on this thread Julie. Holy sh*te, you've been busy !!!
Yes James, I'm a woman on a mission  ;D ;D Also, I have been given a certain amount of time in the workshop, if I go over that time I incur penalty charges  ::) ::) ::)
A proper nurse would have done the bloods and sent them to the lab. Poor bedside manner! :P
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: pistonbroke 66 on October 11, 2017, 04:25:16 PM
I was disproportionately proud of fixing my indicator earth until I read this thread.....!  :P :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 11, 2017, 04:46:39 PM
This thread will be you in a few years time.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: pistonbroke 66 on October 11, 2017, 04:51:17 PM
This thread will be you in a few years time.

 ;D ;D we live in hope !!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 05:00:08 PM
Just catching up on this thread Julie. Holy sh*te, you've been busy !!!
Yes James, I'm a woman on a mission  ;D ;D Also, I have been given a certain amount of time in the workshop, if I go over that time I incur penalty charges  ::) ::) ::)
A proper nurse would have done the bloods and sent them to the lab. Poor bedside manner! :P
Yes Tim, you're most probably right there  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 05:03:30 PM
I was disproportionately proud of fixing my indicator earth until I read this thread.....!  :P :D
We should all be very proud of what we do to keep these old girls on the road, regardless of the simplicity or complexity of the task  :) :) :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 11, 2017, 05:20:05 PM
Not doing much to the bike today but have taken the clocks off to send away for a bit of a spruce up with nice new faces.

I thought I would have a closer look at the cam chain tensioner and assembly. The cam chain tensioner arm (horseshoe) is in excellent condition as shown in the photo yesterday but I will free off the very slight tightness I can feel on the pivot pin as Bryan suggested. The chain tensioner adjuster and the 2 tensioner outer springs are also in good condition so I will use them again along with the chain tensioner holder and dampers.

On the tensioner slipper I can see that the little tabs either side look a little moth eaten and on the guide, there are cracks all the way along its length. I’m going to fit a new slipper and guide anyway but interesting to see the cracks on the surface.

[attachimg=1]

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 12, 2017, 07:21:42 AM
Having met both Julie and Trigger and noticed the glints in eyes the only thing that surprises me is that it isn't half back together already!! Honestly though this is well written and should be a great guide when finished, perhaps Steve could put it in tips when its done. I think the only 400 parts i have are the genuine manual and parts book on CD possibly a set of very bad carbs with broken bits unless i binned them as too bad!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Spitfire on October 12, 2017, 12:17:49 PM
Just read this from the start and as usual I am amazed at the punishment these bikes will take and still run, looking forward to more updates.

Cheers

Dennis
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 12, 2017, 04:59:09 PM
I was thinking the same;  how on earth did those shagged pistons drag Julie to Crich and back.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 12, 2017, 05:08:50 PM
Those shagged pistons have dragged me around for almost 5000 Mike !!!!. Anyway, I'm a true biker at heart, I'm not going to let something like knackered pistons stop me. Don't forget I'm into Brit bikes so I'm used to having bits fall apart, blow up and stop working ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: JamesH on October 12, 2017, 05:59:51 PM
Just imagine how lovely the 400 is going to be once you've sorted the engine Julie...!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 12, 2017, 06:58:06 PM
Just imagine how lovely the 400 is going to be once you've sorted the engine Julie...!!
Yes James, she will be lovely.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 12, 2017, 07:16:05 PM
Managed to get the mullered head stud out today. As Mike the Bike noticed previously, it was well corroded in. We used Ian's (Orcadian) way he mentioned earlier. We clamped the stud in the vice, still attached to the casing, applied plenty of diffused heat and turned the casing on the stud. It took some doing though, plenty of WD40 helped. When it started moving we put it on the bench and got mole grips on it, with more WD40 and eventually it came out.

[attachimg=1]

Now, a question i cannot find the answer to in either the Workshop Manual or Haynes. I know on the CB750's, oil comes up two of the head studs, the centre rears. Does this happen on the CB400's as well?. Not necessarily the centre rears but the two end studs on this engine were not corroded in and came out very easily when I was investigating. I have looked at the oil flow diagram but can't see for sure if this happens or not. Any insight much appreciated.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 12, 2017, 08:40:57 PM
Hi Julie,
I'm really enjoying your regular updates and having just done my spare 400/4 I'll willingly accept the subliminal bollocking I got from you for not sharing this with the forum!  Although I have written many pages on my site with bike and car rebuilds and quite a few articles in Tansha and Jaguar mags, I seem to have lost the enthusiasm for recording all this stuff - although I've taken lots of pics just in case.  Might be the fact that I'm 69 next birthday and if life were just one day long, then it's nearly 23.00 hours!
Your thread has really hit the spot with old hands and newbies alike, so keep up the good work!
Very pleased that you had success with the slightly unorthodox method of stud removal - it's worked many times for me.
Many years ago I bought a knackered old BSA 150 Bantam which kind of ran but wouldn't pull when you tried letting the clutch out.  Only when I stripped the engine did I find there were NO piston rings in it - so I'm not really surprised that your bike actually ran.
On the oil up the studs question, doesn't it go up the two outer ones with those rubber seals between the barrels and head?

Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on October 12, 2017, 09:01:10 PM


Now, a question i cannot find the answer to in either the Workshop Manual or Haynes. I know on the CB750's, oil comes up two of the head studs, the centre rears. Does this happen on the CB400's as well?. Not necessarily the centre rears but the two end studs on this engine were not corroded in and came out very easily when I was investigating. I have looked at the oil flow diagram but can't see for sure if this happens or not. Any insight much appreciated.
[/quote]

just look down the stud holes for drillings going off at angles, if they have the answer is yes
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 12, 2017, 09:04:17 PM
Thanks Ian, I'm pleased you are enjoying reading about my tinkerings, I'm really enjoying the hands on work and sharing it with others, it's good fun.
You have confirmed my suspicions that the oil goes up the two outer head studs, that's why they were nice and free as the oil coming up the thread has stopped any corrosion setting in !!!.
Edit....Yes, I did mutter a bollocking directed at yourself for not sharing your rebuild but I can understand why you didn't  :) :) :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 12, 2017, 10:50:10 PM
I'm used to having bits fall apart, blow up and stop working ;D ;D ;D

Is this a dig at Graham I wonder??  :) :)
;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 13, 2017, 02:00:33 PM
Where do the restrictors fit on the 400. been so long I cant remember, 500,s are in the base dowels
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 13, 2017, 02:03:22 PM
Where do the restrictors fit on the 400. been so long I cant remember, 500,s are in the base dowels
They fit right at the end of the barrels to head Bryan. Marked in green
[attachimg=1][attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 13, 2017, 02:39:06 PM
Are there equivalent holes at the base gasket or are the holes drilled at an angle into a stud hole, isn't clear on base gasket pic. EDIT

Looking at the Motogrid parts list there are dowels in the base gasket at the outsides and I suspect the oil feed is upwards through those then restricted at the head gasket, what I cant see is if there are any O rings at he base joint.
This would mean the oval holes at the studs are for drain down.

It does mean those holes need to be kept super clean on assembly, its easy to get bits of base gasket down the holes which then blocks the restrictors and seizes the cam. I know Julie and Trigger are well aware of this
But I write this for everybody else as it is valid for all the fours
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 13, 2017, 04:20:11 PM
Pictures from bottom to top. The oilway starts (or finishes as I can't quite work out which way it is going yet!!!) in the main bearing housing.
[attachimg=1]

And comes out on the top of the base (see post on page 25 of this thread re inserting an  'O' ring around this dowel )
[attachimg=2]

Up via a dowel between the base and the barrels (dowel not in situ in pic)
[attachimg=3]

Up through the barrels to where the oil control valve is fitted between the top of the barrels and underside of the head ( valve not in situ in pic)
[attachimg=4]

Up through the head
[attachimg=5]

Basically it is in a straight line from bottom to top but the hole on the underside of the head has a minute little shelf just inside.






Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 13, 2017, 04:26:39 PM
And out the other side. This is where the oil pipes fit that I showed in a pic when I first started stripping the engine that spray the cam.

[attachimg=1]

Here is the pic again
[attachimg=2]

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 13, 2017, 10:37:46 PM
Starts at the mains with oil pump pressure and flow, goes upwards till restrictor which cuts down the flow to keep pressure at the crank ends then sprays niftily over the cam, which i al sways thought was a great design.

On the 500 the restrictor is inside the dowel in the base joint which has an O ring round it, they must rely on the dowel being a decent fit and a good gasket seal on the 400
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Seabeowner on October 14, 2017, 10:03:28 AM
Very interesting to see the 400 in so much detail. Thanks for posting. And interesting it's completely different to the 500/550, where not only are the restrictors at the base, but oil is fed to under the camshaft surfaces only and the cam faces are dipped in a bath. Honda either had teams working in pretty much isolation or they were doing a lot of experimentation and we were the guinea pigs.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 14, 2017, 10:24:58 AM
My feeling is that the 400/4 was a later idea/development than the 750/500/550 fours, and experience from the earlier motors led the the cam spraying idea. Done from the design stage they probably hoped it would reduce problems and warranty claims and improve reliability. It would have been prohibitively expensive and disruptive to modify the heads of the earlier models in this way. Just my take on it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 14, 2017, 11:17:16 AM
My feeling is that the 400/4 was a later idea/development than the 750/500/550 fours, and experience from the earlier motors led the the cam spraying idea. Done from the design stage they probably hoped it would reduce problems and warranty claims and improve reliability. It would have been prohibitively expensive and disruptive to modify the heads of the earlier models in this way. Just my take on it.

 I like the 500 cam lubrication,with pressure feed to the journels and oil dip/bath for the lobes and followers ,how does the spray
 work better ?
BUT. very interesting ,love these threads
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 14, 2017, 11:49:16 AM
The 500/550 oil bath works okay, but when the cam is turning at 4000+ rpm at high engine  speeds, centrifugal force will obviously decrease the amount of oil that can cling to the cam lobes compared to a constant spray like the 400 gets, as I said, just my take on Honda's thinking at the time. After all, the 400 system would increase production costs per unit, so they obviously thought it was worth the cost.

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on October 14, 2017, 11:53:27 AM
John,
There is an oil bath of sorts in the 400 head directly below the camshaft. From memory I think only the cam lobes themselves dip into the oil in the bath as the cam spins.
As the oil sprays out of the drillings from the spray bar over the cam it collects in the oil bath to a certain level. When the level is reached the oil runs back down into the engine. Maybe Julie has a photo of the top of the cylinder head to demonstrate the theory?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on October 14, 2017, 12:03:03 PM
Here's a photo of the cylinder head from my engine. The 'oil bath's sit between the cam bearings either side of the cam chain tunnel.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 12:28:24 PM
Here's a photo of the cylinder head from my engine. The 'oil bath's sit between the cam bearings either side of the cam chain tunnel.
Same pic as I would have posted but, such a glorious day here, i have been out for a lovely long, fast ride, looooooovely 😊😊😊
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on October 14, 2017, 12:34:08 PM
I do hope you were not exceeding the speed limit Julie! As a truck driver VOSA have just decided that they can do us for "Historic" offences up to a month old from a tachograph printout
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 12:58:27 PM
I do hope you were not exceeding the speed limit Julie! As a truck driver VOSA have just decided that they can do us for "Historic" offences up to a month old from a tachograph printout
Moi, break the speed limit Bryan, never  ;) ;) ;) I only ever ride as fast as the road conditions and traffic volume allow. Today, the road conditions were perfect and there was no traffic on the roads.....the perfect combination to blow the cobwebs out  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 14, 2017, 03:07:17 PM
I do hope you were not exceeding the speed limit Julie! As a truck driver VOSA have just decided that they can do us for "Historic" offences up to a month old from a tachograph printout
Moi, break the speed limit Bryan, never  ;) ;) ;) I only ever ride as fast as the road conditions and traffic volume allow. Today, the road conditions were perfect and there was no traffic on the roads.....the perfect combination to blow the cobwebs out  ;D ;D


   I agree,been perfect here,and a nice blast at just over 7,000 rpm for about 4 miles cleared the pipes,cobwebs and me out !!!

 mid october and still warm and sunny !! long may it continue !!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Woodside on October 14, 2017, 03:19:25 PM
me too took my old fireblade for an mot this morning...les than a mile from my house just got in and ive clocked up 110 miles....i have been thinking of selling it now im thinking perhaps not
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 03:37:47 PM
me too took my old fireblade for an mot this morning...les than a mile from my house just got in and ive clocked up 110 miles....
So you were out for just over 5 minutes then Jason  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Woodside on October 14, 2017, 03:42:26 PM
hhmm awol 3 hours
almost ended up in brighton
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 04:33:58 PM
John,
There is an oil bath of sorts in the 400 head directly below the camshaft. From memory I think only the cam lobes themselves dip into the oil in the bath as the cam spins.
As the oil sprays out of the drillings from the spray bar over the cam it collects in the oil bath to a certain level. When the level is reached the oil runs back down into the engine. Maybe Julie has a photo of the top of the cylinder head to demonstrate the theory?

I have just put the camshaft back in place to see if I can get any further insight into this. It was impossible to photograph the underside of the lobes in their 'fully down' position and impossible to measure also. To me it looks like there is about 10mm clearance under the lobe to the bottom of the 'bath'. What I did see though is a definite 'tide mark' around the edge of the bath which would suggest that what Laverda120 says is correct, that the cam lobes dip in the oil bath on each revolution and possibly the tip of some of the lobes may sit in oil when the engine is not running (obviously depending on where the cam stops) . What I can't find though is any drain holes out of the baths, so where would the excess oil that is sprayed from the oil arms go when the bath is full?.

Tide mark
[attachimg=1]

And again
[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on October 14, 2017, 04:46:22 PM
Most of it goes down the camchain tunnel.

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 04:49:08 PM
Most of it goes down the camchain tunnel.

Sent from my X6pro using Tapatalk
Ah yes Hairy, I didn't give any thought to that bloody great big hole in the middle  ::) ::) ::) ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 14, 2017, 04:50:32 PM
John,
There is an oil bath of sorts in the 400 head directly below the camshaft. From memory I think only the cam lobes themselves dip into the oil in the bath as the cam spins.
As the oil sprays out of the drillings from the spray bar over the cam it collects in the oil bath to a certain level. When the level is reached the oil runs back down into the engine. Maybe Julie has a photo of the top of the cylinder head to demonstrate the theory?

I have just put the camshaft back in place to see if I can get any further insight into this. It was impossible to photograph the underside of the lobes in their 'fully down' position and impossible to measure also. To me it looks like there is about 10mm clearance under the lobe to the bottom of the 'bath'. What I did see though is a definite 'tide mark' around the edge of the bath which would suggest that what Laverda120 says is correct, that the cam lobes dip in the oil bath on each revolution and possibly the tip of some of the lobes may sit in oil when the engine is not running (obviously depending on where the cam stops) . What I can't find though is any drain holes out of the baths, so where would the excess oil that is sprayed from the oil arms go when the bath is full?.

Tide mark
(Attachment Link)

And again
(Attachment Link)
Like the 500.there is no drain. It is a mini sump to provide oil to the cam after standing. During start up before the oil pressure builds up.a simple method to protect lobes and followers.
During running the oil gets splashed
Arround and lubricants valves. Chain. Before returning to the sump


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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 04:56:22 PM
John,
There is an oil bath of sorts in the 400 head directly below the camshaft. From memory I think only the cam lobes themselves dip into the oil in the bath as the cam spins.
As the oil sprays out of the drillings from the spray bar over the cam it collects in the oil bath to a certain level. When the level is reached the oil runs back down into the engine. Maybe Julie has a photo of the top of the cylinder head to demonstrate the theory?

I have just put the camshaft back in place to see if I can get any further insight into this. It was impossible to photograph the underside of the lobes in their 'fully down' position and impossible to measure also. To me it looks like there is about 10mm clearance under the lobe to the bottom of the 'bath'. What I did see though is a definite 'tide mark' around the edge of the bath which would suggest that what Laverda120 says is correct, that the cam lobes dip in the oil bath on each revolution and possibly the tip of some of the lobes may sit in oil when the engine is not running (obviously depending on where the cam stops) . What I can't find though is any drain holes out of the baths, so where would the excess oil that is sprayed from the oil arms go when the bath is full?.

Tide mark
(Attachment Link)

And again
(Attachment Link)
Like the 500.there is no drain. It is a mini sump to provide oil to the cam after standing. During start up before the oil pressure builds up.a simple method to protect lobes and followers.
During running the oil gets splashed
Arround and lubricants valves. Chain. Before returning to the sump


Sent from my SM-G361F using Tapatalk
Thanks John. I have just found this oil flow chart in the Workshop Manual which helps identify the paths

[attachimg=1]
 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Dave487 on October 14, 2017, 08:31:52 PM
Don't do what I did and fit the restrictors wrong way up, they get bent and when you try to straighten them they break.
They have to go with stem downward.
Luckily I was just doing a dry assembly so spotted it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 14, 2017, 08:41:23 PM
Don't do what I did and fit the restrictors wrong way up, they get bent and when you try to straighten them they break.
They have to go with stem downward.
Luckily I was just doing a dry assembly so spotted it.
Thanks, I will remember that (could someone remind me nearer the time please  ;D ;D ;D)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 16, 2017, 05:25:55 PM
A little more progress today. I have cleaned all the nuts, bolts, washers etc that will be going for re zincing. We use the ‘cement mixer method’. Fill cement mixer with items to be cleaned, add a load of traffic film remove and boiling water and switch machine on. This cleans off all the old oil, grease and dirt. We used to put sharp sand in as well but found it cleaned just as well without.
Then every single item has to be cleaned fully by hand on the electric wire wheel machine. This removes the remainder of the dirt, grease and rust from in the nooks and crannies, including the threads. Dry off on a big tray in the oven for a few minutes. Whatever dirt you leave on will still be there after zincing but hidden temporarily under a nice new layer of zinc, until it starts falling off with the dirt. I only had a fairly small amount to clean so threw them in the mixer with the huge amount Trigger was cleaning and now they have all been thrown in big buckets together ready for taking to the platers. The fun will start when we collect them from the platers as they all have to be sorted out and there are 100’s and 100’s of them !!!

Another thing I did was take a good look at the rocker arms. On the CB400/4 you remove the rocker arm shafts by removing the cap nut and screwing a 10mm (1.25 pitch) bolt in the end of the shaft and pull. The rocker arms come off the shaft with the springs.
All it says in the Haynes Manual and the workshop manual is ‘Examine the ends of the rocker arms for damage and examine the tappet’. No real explanation of what ‘damage’ you are looking for. I have found some rocker arms in the workshop from a CB750 and compared mine with those. Mine look a lot better !!. There are no ridges or deep scratches, therefore I will be using mine again when the engine is rebuilt.

From the CB400

[attachimg=1]
[attachimg=2]
[attachimg=3]

From a CB750

[attachimg=4]
[attachimg=5]

I won't be posting much on this thread for quite a few weeks. The casings go to the acid strippers in about 2 weeks and will be there at least another 2 weeks and I can't do anything else until I get them back and prepared and painted. I will be ordering parts though. I'm off on my travels with my Nursey girlfriends to Seville in about 3 1/2 weeks, so at least Trigger will get his workshops back for a while !!!.


Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 16, 2017, 06:11:38 PM
Apart from the obvious problem you have with the engine,  and as you feel it's not been rebuilt prior to this, it appears that it has been run on oil of decent condition as all the tell tale wear points seem in very good condition.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 16, 2017, 06:21:00 PM
Apart from the obvious problem you have with the engine,  and as you feel it's not been rebuilt prior to this, it appears that it has been run on oil of decent condition as all the tell tale wear points seem in very good condition.
Yes, it's a shame that the pistons are so bad as they really aren't representative of the rest of the engine which is looking really well maintained. The engine has definitely never been apart before. I'm hoping that all the shells, bearings etc measure up ok because they are showing no signs of damage at all.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 16, 2017, 07:26:49 PM
Have you got any theory as to how the pistons got like that?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 16, 2017, 09:45:59 PM
Have you got any theory as to how the pistons got like that?
Well Mike, the pistons got in that state due to uncontrolled detonation with no rings. The rings had obviously started breaking up and the damage to the pistons and the rings just escalated from there. The burnt areas down the side of the pistons show that combustion was getting down the side of the pistons as the rings (or lack of them!!!) were not containing everything in the combustion chamber. Having looked very closely at the bores again, I can see a few vertical score marks near the top but, I think this is where the broken piston rings, still in the lands, were scoring. I have looked very, very carefully and can see no evidence of water damage. There is none of the tell tale half moon water marks that you should see if the bike was stored on the side stand for years. There is also no water marks in the same places on #1 and #4 or #2 and #3, which would rule out water ingress whilst on the centre stand. None of this explains why #4 piston/ rings has been totally unaffected, as they move in pairs as we know but this has also happened to 3 pistons on Craig400's bike. Now, if as was suggested, the bike may have run very lean on pods in the past, then reverted to a standard airbox setup, but no adjustment made to the mixture, why still no damage to #4?.
The consensus is that this damage occurred a very long time ago, as seen by the amount of carbon where the rings should have been and one day it was all going rear it's ugly head. The problem is, there is no evidence left to analyse as the main damage occurred so long ago. Yes, we can say exactly what has happened to the pistons because they are there in front of us but what the original cause of the damage was, I don't think we will ever know.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on October 16, 2017, 09:55:58 PM
I was thinking about the damaged pistons today and remembered my 2stroke Go kart had almost identical damage except the rings stayed in one piece. It was running far to lean due to a damaged diaphragm.
My brothers KH125 did exactly the same thing when his mates fiddled with the carb aswell 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 16, 2017, 11:04:28 PM
Now there's a bunch of people that work more closely with detonation Mick. They often use different shaped combustion head shapes with differing squish bands to control it.

It's often seen on isolated or any number of cylinders on V8 cars running high power setups. It's by no means odd to get some cylinders to detonate and some not even when all running through one carb.
Those applications they try and get all the spark plug electrodes facing the same way in the heads to avoid any masking of the spark if not facing the flame advance direction of combustion.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 17, 2017, 01:27:30 PM
How did the piston rings get like that I wonder.  I can understand them snapping when installed,  or when the barrels are fitted, but once fitted, how would they break?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on October 17, 2017, 05:30:22 PM
I think you're entirely right Mike.
If you look at the pistons and the witness marks that have been carved out of them by the rings then you can see in some of them where the piston land material has let go,  this has resulted in the part of the ring that's still attached to bend and flex in an arc which has cut a corresponding hole at its free end that looks like a metronome.
To me this illustrates that the piston material went soft through heat and prior to the ring being broken. Under extreme heat exposure the rings can anneal as well. Spring steel is annealed by heating up over critical temperature,  but not melting,  then leaving to cool gently over a period of time. As opposed to hardening via heat and sharp quenching.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 17, 2017, 06:05:06 PM
Thanks for answering Mikes question K2-K6. I have been thinking all day about the reasons for the broken rings. I was swaying between the damage to the top of the pistons causing the rings to break or the rings breaking first and leading to the damage to the top of the pistons. But, my extremely limited knowledge of these things, which quite honestly, would fit on the back of a postage stamp, meant I did not know the answer for certain. I was hoping someone like you would come along to explain....and you did. Thank you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 18, 2017, 06:50:53 PM
Back to the subject of water damage in the bores, or lack of it in the case of my 400/4. I found a barrel in the workshop, from a CB750, that clearly shows a water mark, half moon shape, where the bike had been left standing for a long period of time on the side stand. The water had been sitting on the top of the piston. On this particular barrel, the watermark was not evident until the bore had been honed.

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 22, 2017, 12:02:26 PM
Took the oil pump apart this morning. I was concerned that with the amount of swarf  that may have been going around that some damage may have occurred but no, it’s perfect inside. No scoring or abrasion damage evident . I measured the clearance, rotor to housing service limit is 0.35mm max, mine measured 0.10mm. Also measured the inner to outer rotor clearance, service limit is 0.30 mm max and mine measured 0.08 mm, 0.09 mm, 0.09 mm  and 0.10mm on the four points. I’m very pleased with all that.

Even though the pump had new ‘O’ rings fitted less than 500 miles ago due to a leak caused by old, brittle rubber, I reassembled it using new ‘O’ rings as I have oil pump ‘O’ ring kits here for the CB400/4 so would have been silly not to fit new again. Pump now all ready to bolt back on, when I get to that stage.

[attachimg=1][attachimg=2][attachimg=3][attachimg=5]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on October 22, 2017, 08:29:10 PM
The filtration system has obviously been doing its job, the pump certainly seems not to have ingested anything nasty and no doubt all the oilways will have their bungs removed and be checked.

Has Trig got a new camera? The detail is excellent!

Not long now!  Great work,

Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 22, 2017, 08:45:20 PM
Thanks Ian.
No, Trig is still using his camera with the out of focus, frosted lens. I'm taking these pictures with my £25 mobile phone. They are really clear.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: rockvegas400 on October 22, 2017, 11:18:25 PM
Julie do you know what size the o rings are in your oil pump kit? I'm interested to see if I can buy them from a local supplier.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on October 22, 2017, 11:37:37 PM
Julie do you know what size the o rings are in your oil pump kit? I'm interested to see if I can buy them from a local supplier.
Don't bother. Support Trigger. He keeps these sohc bikes running. And at a reasonable cost

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 31, 2017, 06:54:38 PM
[attachimg=1]Have been and collected loads of blingy bits from the platers today. These are some of the nuts and bolts we had done and somewhere in this pile are the bolts from my engine, not many though as most of the ones fitted were Allen screws which I have done away with as I'm going to fit original machine screws.....all I need to do now is find the ones for my bike in this little lot  :'( :'( :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on October 31, 2017, 09:50:46 PM
That's a nice haul, must feel like Christmas has come early.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on October 31, 2017, 10:00:33 PM
That's a nice haul, must feel like Christmas has come early.
It was a bit like that Mike. This was about half what we had plated this time, a very good job done by them again. I have found all of my bolts, except one of the main crankcase bolts, UBS M8 x14, I can only find 5 but I'm sure there should be 6.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on November 01, 2017, 12:42:18 PM
That's a nice haul, must feel like Christmas has come early.
It was a bit like that Mike. This was about half what we had plated this time, a very good job done by them again. I have found all of my bolts, except one of the main crankcase bolts, UBS M8 x14, I can only find 5 but I'm sure there should be 6.
Graham will be hiding it so he can fit the last piece of the jigsaw ;) ;) ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 01, 2017, 12:54:50 PM
That's a nice haul, must feel like Christmas has come early.
It was a bit like that Mike. This was about half what we had plated this time, a very good job done by them again. I have found all of my bolts, except one of the main crankcase bolts, UBS M8 x14, I can only find 5 but I'm sure there should be 6.
Graham will be hiding it so he can fit the last piece of the jigsaw ;) ;) ;D
You'll be right there Paul. He will suddenly find it, fit it and then say 'I told you you wouldn't be able to do it without me'   >:( >:( >:(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on November 01, 2017, 01:22:31 PM
That's a nice haul, must feel like Christmas has come early.
It was a bit like that Mike. This was about half what we had plated this time, a very good job done by them again. I have found all of my bolts, except one of the main crankcase bolts, UBS M8 x14, I can only find 5 but I'm sure there should be 6.
Graham will be hiding it so he can fit the last piece of the jigsaw ;) ;) ;D
You'll be right there Paul. He will suddenly find it, fit it and then say 'I told you you wouldn't be able to do it without me'   >:( >:( >:(


  Laughs !!!! -))))))
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on November 01, 2017, 04:55:37 PM
And then you can do the same to one of Trigger's rebuilds.   ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 01, 2017, 05:27:57 PM
Haha, now there's a thought Mike. The problem is that Trig knows the exact size of every single nut, bolt, washer, dowel, O ring, spring, cog and everything else, off by heart for all the Honda SOHC engines, and he knows where every single part goes without looking at a manual or microfiche. He would know if something was missing just by looking at the pile.....he would also know it was me that had 'moved' it  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on November 01, 2017, 06:04:12 PM
Reminds me of Rain Man
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 01, 2017, 06:23:16 PM
Reminds me of Rain Man
Your right there Mike, I think Graham is Raymond Babbitts twin  ;D ;D ;D :'( :'( :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 02, 2017, 03:55:46 PM
All the outer casings in the crate to take to the acid strippers tomorrow. Hopefully they will be back in about 2 weeks.
[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 10, 2017, 11:40:19 AM
Whilst waiting for the engine cases to be returned from the acid strippers, I have been ordering the parts I will need for the rebuild.
One of the items I now have here is the primary drive chain. I posted a photo of the original primary chain and Oddjob suggested I put the old chain next to the new to show the comparison.

Original Hy Vo chain fitted to the engine.

[attachimg=1]

Now the original next to the new Hy Vo

[attachimg=2]

There is no damage as such to the old chain but it's lost it's structure just through normal  wear.

I have also now got the head stud to replace the one that had to be mullered to remove it, the new supporting grommets for the oil jet tubes that spray the camshaft as one was broken, the other was very brittle also so decided to replace both. Have got gasket set, engine oil seals, cam chain etc etc etc, so gradually collecting all the bits I need.

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 10, 2017, 09:13:30 PM
For those that have never seen a Hy-Vo up close and personal, this is what it looks like.
[attachimg=1]
[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 25, 2017, 04:06:28 PM
Cor blimey, don't these things take a long time. In my head I wanted to have this engine rebuilt by now......but back I the real world my engine cases have now been acid stripped. This has removed all the old paint and oil, just a quick blow over with the soda next week sometime to remove any corrosion and they will be ready for painting.

Some pics of a few of the bits.
[attachimg=1][attachimg=2][attachimg=3]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Trigger on November 25, 2017, 09:35:55 PM
Reminds me of Rain Man

More like Rab C Nesbitt  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on November 25, 2017, 10:29:54 PM
Reminds me of Rain Man

More like Rab C Nesbitt  ;D ;D ;D
I'd be careful Trig, upset Julie too much you may end up being the twin of John Bobbit

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on November 25, 2017, 11:01:19 PM
 ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 01, 2017, 07:04:56 PM
More progress. Main cases painted and cured so I can start rebuilding the bottom end.
[attachimg=1]
[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 01, 2017, 07:33:34 PM
Looks nice.

That's one of the best bits I think, starting the build with things all clean any prepared.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: 3scs on December 01, 2017, 08:18:03 PM
That looks good if it’s not top secret what has been done to get to that condition
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 01, 2017, 08:27:36 PM
That looks good if it’s not top secret what has been done to get to that condition
No secret. Hot wash to remove all grease etc.  Acid dipped to remove all old paint / oil. Another hot wash. Soda blast and hand finish to remove any old corrosion that may be left in the nooks and crannies. Painted with engine enamel, air cured for 24 hours then final cure in the oven. The good outcome is definitely due to the prep.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 01, 2017, 08:34:14 PM
someone else is doing up a 400/4

 not as good condition as your little gem

https://www.facebook.com/SilverSpares/posts/1763265910351260
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 01, 2017, 08:39:59 PM
someone else is doing up a 400/4

 not as good condition as your little gem

https://www.facebook.com/SilverSpares/posts/1763265910351260
No, that will never be as good as my Hettie. Sand in the sump, people will not learn  ::) ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on December 01, 2017, 11:32:24 PM
That looks good if it’s not top secret what has been done to get to that condition
No secret. Hot wash to remove all grease etc.  Acid dipped to remove all old paint / oil. Another hot wash. Soda blast and hand finish to remove any old corrosion that may be left in the nooks and crannies. Painted with engine enamel, air cured for 24 hours then final cure in the oven. The good outcome is definitely due to the prep.

Julie, was final painting farmed out or DIY?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 01, 2017, 11:38:59 PM
That looks good if it’s not top secret what has been done to get to that condition
No secret. Hot wash to remove all grease etc.  Acid dipped to remove all old paint / oil. Another hot wash. Soda blast and hand finish to remove any old corrosion that may be left in the nooks and crannies. Painted with engine enamel, air cured for 24 hours then final cure in the oven. The good outcome is definitely due to the prep.

Julie, was final painting farmed out or DIY?

Trigger did it and he has many engines on the paint list at the moment but, I did squeeze mine in.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on December 02, 2017, 07:53:16 AM
That looks good if it’s not top secret what has been done to get to that condition
No secret. Hot wash to remove all grease etc.  Acid dipped to remove all old paint / oil. Another hot wash. Soda blast and hand finish to remove any old corrosion that may be left in the nooks and crannies. Painted with engine enamel, air cured for 24 hours then final cure in the oven. The good outcome is definitely due to the prep.

Julie, was final painting farmed out or DIY?

Trigger and he has many engines on the paint list at the moment but, I did squeeze mine in.

Mmm favouritism then.... Rattle can job or proper set up?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 02, 2017, 08:39:52 AM
That looks good if it’s not top secret what has been done to get to that condition
No secret. Hot wash to remove all grease etc.  Acid dipped to remove all old paint / oil. Another hot wash. Soda blast and hand finish to remove any old corrosion that may be left in the nooks and crannies. Painted with engine enamel, air cured for 24 hours then final cure in the oven. The good outcome is definitely due to the prep.

Julie, was final painting farmed out or DIY?

Trigger and he has many engines on the paint list at the moment but, I did squeeze mine in.

Mmm favouritism then.... Rattle can job or proper set up?
Favouritism, ha, your having a laugh Tim. Customers come first and as I'm told regularly, I'm not a customer   ::) Rattle can enamel. Trig heats the cases and the paint  before applying, it gives a much better adherence and finish.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 05, 2017, 10:35:55 AM

Online K2-K6
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400 Four detonation
« on: Today at 09:05:04 AM »
QuoteModifyRemove
Alright,  I know I " go on about it" but been looking at why I feel detonation can easily occur on this engine given the right / wrong conditions.

As others pointed out you normally associate lean mixture with something like this,  which is not obviously the case if jetted properly,  you'd have thought?
A characteristic of slide carbs is that you can create it with how you ride,  even if setup is correct.


Above should be a dyno trace that Jensen has kindly shared of his 400 Four running in 4th gear with throttle rolled open in that one gear to build the power curve you see in top traces.

The really interesting bit is the lower trace,  left scale is mixture with rpm along the bottom. It's obvious from that peak leading up to 4000rpm that it's running toward an over lean condition. Complete burn is considered to be 14.7 parts air to 1 part fuel. Most engines won't get that close. During acceleration you'd expect closer to 12 to 1 to make it move,  with cruising state in between the two.
It's not a wrong setting on here,  just characteristic of running from low rpm to high in one gear which is needed for the dyno plot.

What it does is the vacuum the engine draws at low rpm with throttle wide open cannot match the flow the carb venturi is making,  resulting in loss of vac on the main jet,  and so less fuel than ideal is pulled from float chambers ( it's this bit that PD carbs fill in with accelerator pump,  clever a?)  you can't jet your way out of it as the carb and main jet is almost fully open. It's really a failure of slide carbs used in this way and what would be termed "lugging " the motor in high gear.

In addition,  the ignition advance reaches max around 3000rpm and quite early for full load application ( more suited to cruising on light throttle to give good economy)  so in that lean peak area you've also got probably too much advance for a short period.

Put those conditions together,  perhaps riding along into a headwind,  fith or sixth gear,  trying to keep up speed at lowered rpm and you've got classic detonation. Riders with experience would recognise it's not pulling properly,  but if the circumstances are held like that without the engine accelerating through that, it will most likely detonate. It'll only take a few minutes like that to start the destruction of the pistons and rings.

You can't jet it differently,  it's just how you ride it. They need to be revved if you want them to go.
You've either got to back down the throttle or drop gears and spin it to higher revs.
Modify message
[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 05, 2017, 12:00:36 PM
The above post is copied from another thread that I've started with a relevant heading to make it easy to find in future.

http://www.sohc.co.uk/index.php/topic,14609.msg118849/topicseen.html#new

Thought I'd better explain as Julie requested that I post it over here otherwise it may look a bit like random ranting by me. ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 05, 2017, 02:04:42 PM
That's really interesting Nigel. So, going back to the mess on my pistons / rings on my engine strip thread, it would make sense to me how my engine got in such a state. If a PO had not ridden it as the bike likes to be ridden for optimum air / fuel mixture ie, high revs and the engine 'pulling' a majority of the time then it makes total sense how the damage had occurred. I have said many times that the CB400/4 likes to be ridden like a 2 stroke, high revs and minimal lugging and I can see how riding it for long periods in the wrong gear / too lower revs can start a chain of events leading to damage.
A lot of riders think the CB400/4, being a smallish engines bike, are easy to ride but it's totally the opposite in fact, they are bloody hard work if ridden properly, definitely not a bike for the cruiser or the lazy rider.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 05, 2017, 03:01:59 PM
All the above makes total sense to me of how, after detonation, the pistons/ rings where damaged to such a great extent on 3 of the pistons/ rings. But, that still does not explain why 1 piston and rings were totally unaffected. I'm now thinking that this was the end result of a chain of events. I think, as Mr Davo and others have commented,  the bike having had been left standing for at least 8 years prior to me owning it, that we know of, rust had started forming between the rings and the bores and someone had unseized it either, forcibly or just by trying to start the engine, the rings sustained damage and the process of destruction had begun. I think the unaffected piston was due to the stroke the piston was on when the bike was laid up.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 05, 2017, 04:42:10 PM
It may be linked to storage and stuck rings,  you'd not want to rule out something obvious if you were to recommisiion an old engine. It's possible it could be a reverse of the logic though. If you had the rings stuck on one piston,  then the resulting loss of compression would make that faulty one less likely to detonate. Float height on one carb or leaking float valve would make it run rich,  possibly on one pot. Even something as simple as having one plug with it's gap facing a different way in the chamber will have some influence.

It's something that can easily be done that will completely wreck pistons in even the most pristine condition. I stood in on a dyno run for quite a radical tuned car engine in which they were running it under load to make sure they didn't get it detonating in use. Completing igniting swings ( running at varied static advance to make sure they had the most advance they could use while defining what's too far so they could get ideal setting) it was running close to flat out when it started to exhibit that. It sounds like something from general description to be minor when described as "pinking" but when standing that close to it,  it really does sound like you're listening to the beginning of an explosion! I stood outside the doorway as I imagined being hit by bits of hot engine it sounded so bad. It was only a second or two as they obviously wanted to avoid any damage,  but nevertheless gave an indication of the violence that it can exert if left unchecked.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 07, 2017, 05:16:16 PM
I re assembled the crankshaft today. Even though initially I had thought there would be signs of damage and wear on the shells due to the break up of the pistons / rings and the debris going around the engine, all the engine shells, to my amazement show no sign of damage, or excessive wear and measure well within the service limit. Therefore I am using all the original shells throughout the re build.

I am so scared of getting anything out of sequence, or position, or put back in the wrong place, I have to keep everything in order, or just 'so', hence the conrods on a handy screwdriver, in order !!!

I blew all the oilways out with the airline to make certain they were thoroughly clean, even though I had given the crank a thorough clean previously. I also cleaned, again, all the bearings, both front and back to make sure there was no contamination when I fitted the shells to the con rods. I then covered the shells with bearing guard, torqued up the conrod bolts and today I am using pink engineers paint as the visual reference to myself that I have torqued the bolts.

[attachimg=1]
[attachimg=2]
[attachimg=3]
[attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 07, 2017, 05:26:19 PM
I then set about fitting the top and bottom crank case shells, which I had numbered and bagged up on strip down as top and bottom. Once again, I gave them a thorough clean, again. I fitted the 2 primary chain guards, with the indent facing backwards towards the gearbox end. I also fitted the reduction gear and the photo shows the stopper bolt and the lock washer that holds the gear shaft in place.
[attachimg=1]
[attachimg=2]
[attachimg=3]

All in, not a bad bit of work today. I'm very slow but want to get it right (obviously!!!) but also want to learn as much as I can throughout the process. I also have to keep thinking what is position No1, for example, as at the moment the top case, being upside down is, in effect, back to front but I'm gradually getting the knack. It's lovely working with everything nice and clean.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on December 07, 2017, 06:09:01 PM
Your photos are spot on.  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 07, 2017, 06:22:16 PM
Very nice.

I can see a problem though,  that mug has no tea in it,  may have to attend Guy Martin training course on the benefits of tea during engine building  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 08, 2017, 07:27:25 AM
Its also way too small, you need a proper Lancashire pint pot!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on December 08, 2017, 08:05:13 AM
Looking good Julie.
Word of warning for you about UPS delivering your CMS parts, you have to home when they deliver as CMS insist on your specific signature. They will not deliver to a neighbour even if you ask them to. After three failed attempts at delivery you have to collect them from the UPS depot.
Don't ask me how I know this  >:(!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on December 08, 2017, 08:10:18 AM
Very nice.

I can see a problem though,  that mug has no tea in it,  may have to attend Guy Martin training course on the benefits of tea during engine building  ;D
Its not tea its Linconshire potatoe Vodka☺
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Trigger on December 08, 2017, 08:24:38 AM
Looking good Julie.
Word of warning for you about UPS delivering your CMS parts, you have to home when they deliver as CMS insist on your specific signature. They will not deliver to a neighbour even if you ask them to. After three failed attempts at delivery you have to collect them from the UPS depot.
Don't ask me how I know this  >:(!

There is a good legal argument if a delivery company do not deliver.
1) You paid for delivery to the stated address.
2) They did not inform you of a delivery time or date,
3) Send a invoice for your time and fuel costs if you had to collect or a invoice if you sent a courier to collect.

My UPS delivery guy has learnt to try the house first and if no one in, then bang on the workshop door as it is on the property as the delivery address  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: andut on December 08, 2017, 08:40:20 AM
Looking good Julie - glad I'm not the only one who gets confused with cylinder order when the crankcases are upside down - always a good idea to label parts when disassembling as you have done and then double / triple check on reassembly !

Won't be long before you fire it up and enjoy the moment of triumph...........  followed by a few hundred miles of needlessly worrying about every noise and vibration (or is that just me ?)

Good luck with the rest of the build !

Andy
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: GiannisFour on December 08, 2017, 07:39:51 PM
Nice work Julie, keep us posted!
Next winter will be my turn with my 400  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 08, 2017, 09:20:57 PM
Bloody helll Ken, I have enough trouble focusing and concentrating on this rebuild without the aid of potato vodka !!!. Tea and coffee will do just fine.....until I have finished the rebuild anyway ☺☺☺☺☺
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hondarc166 on December 10, 2017, 02:09:04 PM
looking good Julie  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 10, 2017, 05:01:39 PM
Re assembled the gearbox this morning, installed the kickstart mechanism and started changing the rubber dampers on the primary drive. Fitted crankshaft and primary and cam chain.

Started off by installing the drum assembly.The gear box dogs, or forks, go on the shift fork guide shaft. The dogs are marked L,C and R to identify which one goes where. The shaft is then secured externally with a lock washer and a set plate.

When installing the gearshift drum and gears it has to be done in the neutral position. The photo shows through to a brass (I think it's brass) point where the neutral switch would make contact, seeing this denotes that the gears are in the neutral position.

The main shaft and counter shaft can then be installed making sure the dogs all locate where they should be. Before installing, I took the 2 needle bearings apart and packed them with grease and greased everything else that moved.

The drum assembly in situ.
[attachimg=1]

The gearbox dogs on the shaft. This pic also shows the half rings in situ and guide pins for the bearings on the main shaft and counter shaft

[attachimg=2]

The shaft secured externally with the lock washer and set plate

[attachimg=3]

The small brass? point showing the drum in the neutral position

[attachimg=4]

All assembled with new oil seals and bearing guard applied to bearing surfaces.

[attachimg=5]

Before I actually join the crank cases together, I will put a smear of Hondabond on the oil seals on the main and counter shafts.

I found this quite difficult this morning and I did have to get Trigger to explain and help me. I just could not understand how all the cogs moved on the 2 shafts and meshed together. I understood the fundamentals of the drum and dogs but it wasn't until it was assembled and he was going from 1st, through neutral and up to 6th gear that I could understand it as I could see it working in front of me. Anyway, it all seems to be meshing together very easily and nice and smooth. I could do it myself now, having been shown the workings, it makes sense.


Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 10, 2017, 05:10:57 PM
I also installed the kick start mechanism.

The pics show it in place and also show the hairpin on the spring in the crank case stopper grove and the other end of the spring attached to the crankcase rib.

[attachimg=1]

[attachimg=2]

On the primary shaft, I have taken the primary driven sprocket apart to fit the 8 new rubber dampers. You can see the internal workings of the sprocket and how the dampers fit in. The dampers in the picture are in fact some of the old ones.

[attachimg=3]
[attachimg=4]
[attachimg=5]

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 10, 2017, 05:21:22 PM
Finally, I fitted the primary chain and cam chain to the crank and installed with new oil seals on the ends of the crank shaft.
[attachimg=1]

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 10, 2017, 07:17:57 PM
looking very good.

  can I ask why you use grease ,when engine oil will lubricate the needle bearing in usage ??

help educate a simple bloke
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 10, 2017, 07:27:50 PM
I have just asked Trig and he says the grease will allow the bearing to move freely before any oil gets there. He says all moving surfaces should be coated with something. It was more of a smear than packed out actually, I was over exaggerating 😁😁😁
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on December 10, 2017, 09:21:13 PM
All looking good Julie, keep the pictures coming  :D :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 11, 2017, 08:06:45 AM
I always use grease, frequently coppaslip as if you use oil then don't run the engine for a while it dries out
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on December 11, 2017, 08:35:39 AM
I used that black grease stuff in a yellow tube, can't think what it's called.   It's used specifically for newly built engines.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on December 11, 2017, 01:16:57 PM
Looking really good Julie.  That's a nice clean workshop. Great to see photos of a rebuild.
Mike, I think the assembly grease is Graphogen, 27 pounds for a large tube that will last for years!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 11, 2017, 01:57:22 PM
Looking really good Julie.  That's a nice clean workshop. Great to see photos of a rebuild.
Mike, I think the assembly grease is Graphogen, 27 pounds for a large tube that will last for years!
The engine building room is cleaner than an operating theatre !!. Its that clean I am only allowed in there with Tea in a clean mug, I'm not allowed to use the same mug twice  ;D ;D ;D
Graphogen, so I have been informed recently should only be used on new metal surfaces, to help them bed in. (I think that's what he said, I probably wasn't listening properly......again  ::) ::) ::))
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on December 11, 2017, 02:36:08 PM
You can also use monosodium disulphode or molyslip- at least that's what I think it's called. I bought a few tubes from a local factory clearance years ago as I was doing a bmw engine rebuild ( actually ended up doing 2 as I spent a fortune doing 1, then found a full kit of parts, all crank 're grinding etc done and twin plugging conversion done too which was on my to do list at a bargin price, the other engine is still sat in my loft, having never run. One day it may become a trike.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 11, 2017, 04:10:42 PM
The rest of the cases have now been painted and cured.

[attachimg=1]

The damage to the combustion chambers on cylinders 2,3 and 4 has been tidied up. Considering what a state they were in I think they have come up very well.

Now

[attachimg=2]

Before

[attachimg=3]

I am in line (although at the end of a very long line !!) to have the head skimmed and the valve seats 'kiss' cut.

[attachimg=4]

Trig has also dropped the front forks out for me today, so I can take them apart, do whatever needs doing, fit new seals, refill with oil and refit to the bike. Hopefully this will stop the feeling I get sometimes that the forks, when fully compressed, are actually getting stuck in the down position. (Link to my fork overhaul thread http://www.sohc.co.uk/index.php/topic,14717.0.html).He is also going to skim the front brake disk as part of the never ending quest to stop the front brake squeaking as everything else he has done has made no difference at all. It's fine some days and not others, a bloody pain in the arse.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on December 11, 2017, 10:26:40 PM
End of a long que Julie, there must be something you can do to get to the front ;) ;) ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 11, 2017, 10:32:54 PM
End of a long que Julie, there must be something you can do to get to the front ;) ;) ;D ;D
Everything I have tried so far Paul has failed. But, I will persevere in the hope he will get the hump with me keep whinging on about it and do it just to shut me up 😂😂😂😂. Then, I will need to join another queue for the rebore.........it's never ending 😥😥😥😥😥
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on December 12, 2017, 08:12:45 AM
Knowing Graham just keep getting in his way and talking too him ;)
You could always as for them for Christmas.
Save him spending the 99p on you  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: MCTID on December 12, 2017, 08:14:59 AM
There is a saying Julie.....'Blessed is he whose cause is just.......but thrice blessed he, who gets in first'.

If you get the address of the Machinist and offer to take your parts - and Triggers 'bits' over there yourself.......thus saving Trig valuable travelling time, I'm sure that will help solve the delay.

Suitable fluttering of the eyelashes and a plaintive female voice also helps.

Good luck.....and a very Happy Christmas to you both.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 12, 2017, 08:31:23 AM
There is a saying Julie.....'Blessed is he whose cause is just.......but thrice blessed he, who gets in first'.

If you get the address of the Machinist and offer to take your parts - and Triggers 'bits' over there yourself.......thus saving Trig valuable travelling time, I'm sure that will help solve the delay.

Suitable fluttering of the eyelashes and a plaintive female voice also helps.

Good luck.....and a very Happy Christmas to you both.
This is the problem Alan, Trigger is the machinist !!!. He is doing all my machine work for me. I am ever hopeful that he will take pity on me very soon.
Merry Christmas to you and yours Alan.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 12, 2017, 08:38:23 AM
Knowing Graham just keep getting in his way and talking too him ;)
You could always as for them for Christmas.
Save him spending the 99p on you  ;D ;D ;D
Paul. Graham does not do Christmas in any shape or form. Being a Monday this year, it will be a normal working day. He will definitely not buy me a present and no Christmas card either. I still put up a tree and cook a Christmas dinner though, just to wind him up.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on December 12, 2017, 09:11:35 AM
I'm with Graham on this one nothing more depressing than tinsel and plastic trees.
I would normally spend Christmas day with family but this year they have all abandoned me.
Not to sure if that's a good thing or not.  :-\
 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on December 12, 2017, 10:24:51 AM
I'm with Graham on this one nothing more depressing than tinsel and plastic trees.
I would normally spend Christmas day with family but this year they have all abandoned me.
Not to sure if that's a good thing or not.  :-\
  Same here, I hate xmas with a vengeance! I'm not a believer of any religion, and to me it would be totally hypocritical to celebrate a religious festival. Every year Mrs Hairy and our daughter go to spend 2 weeks at her mum's in Cambridge, leaving me to do my own thing. Usual thing for me is to order masses of Indian food to be delivered on the 24th, stuff my face with it, keep the rest in the fridge to re heat over the next couple of days, and by the 27th, a meat Phall that has been sitting in it's sauce and spices for a couple of days tastes even better than when delivered! ;D ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on December 12, 2017, 01:41:10 PM
I'm with Graham on this one nothing more depressing than tinsel and plastic trees.
I would normally spend Christmas day with family but this year they have all abandoned me.
Not to sure if that's a good thing or not.  :-\
You mean you don't do Christmas but you can't understand why they have abandoned you ;D ;D ;)
We need a new scrooge emogi ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Orcade-Ian on December 12, 2017, 06:47:01 PM
Another Bah, Humbug! member here!
My birthday is in June and I only celebrate on the day, so why do we have to have all this crap starting in September supposedly to celebrate a birth?
Glad when it’s all over for anther 8 months.

Ian
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on December 12, 2017, 06:59:55 PM
What have I started now  ;D
For God sake Julie pull your finger out and get this thread back on track  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 12, 2017, 07:33:58 PM
Another Bah, Humbug! member here!
My birthday is in June and I only celebrate on the day, so why do we have to have all this crap starting in September supposedly to celebrate a birth?
Glad when it’s all over for anther 8 months.

Ian
My birthday is also June. So I see Xmas as a perfect excuse to have a
+6month party.
Others may think it's for Xmas. But I
know better!
Any excuse for a party

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 12, 2017, 07:38:31 PM
What have I started now  ;D
For God sake Julie pull your finger out and get this thread back on track  ;D ;D
I will tomorrow I'm sure but it's your fault, you always make my threads stray, or should that be fray  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 13, 2017, 07:54:09 AM
I always celebrate Quasimodo's birthday, as no bugger knows when it is you can celebrate as often as you want!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Moorey on December 13, 2017, 06:31:45 PM
It's a holiday, what's not to like about any holiday.  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on December 13, 2017, 06:49:51 PM
It's a holiday, what's not to like about any holiday.  ;D
Every shop you need closed, postal and courier companies in meltdown and items you want/need being delayed/lost, etc etc
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 13, 2017, 07:26:44 PM
I was talking to Trigger about the mess he cleaned up for me in the 3 combustion chambers that had sustained damage. Most of the damage was caused by detonation as we know (Wrong, see note below !!!). He also found fragments of the broken rings embedded in the alloy, which he was able to pick out.

I have circled some of the holes left after the ring fragments had been removed from # 3 & 4. In real life the holes are actually very small.

[attachimg=1]

And if you look closely at the original photos, you can just see the penetration holes amongst the rest of the carnage.

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 13, 2017, 08:02:03 PM



   I am surprised,previously any piston that has had ring damage were the ring has escaped upwards and got caught
in the squish band locks like the heads that you have not marked .

 most of my previous experience has been with small 2 strokes,but I did have 1 pot do that on the Honda
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 13, 2017, 08:14:58 PM



   I am surprised,previously any piston that has had ring damage were the ring has escaped upwards and got caught
in the squish band locks like the heads that you have not marked .

 most of my previous experience has been with small 2 strokes,but I did have 1 pot do that on the Honda
You are totally right John, I wrote that wrong. This is all broken ring damage, not detonation  damage silly me  :-[ :-[ :-[
Edit....I was trying to do 3 things when I wrote the above, thinking, breathing and standing up.I seem to have lost the art of multitasking 😂😂😂😂😂
Hairy don't you dare say a word 😢😢😢😢😢
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: SteveW on December 13, 2017, 09:15:51 PM
There is a head off a 550 currently on Ebay with the same damage, but only on #2.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 13, 2017, 09:20:33 PM
There is a head off a 550 currently on Ebay with the same damage, but only on #2.
I would have been a happy bunny if only 1 of mine had damage instead of 3 !!!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on December 13, 2017, 10:20:54 PM
No you wouldn't.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 13, 2017, 10:44:57 PM
No you wouldn't.
True
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 14, 2017, 07:49:50 PM
Finished assembling the bottom end today.
First to go back in was the camchain tensioner. Here is a photo showing all the parts

[attachimg=1]

The push bar has 1 flat side which faces upwards and the tensioner adjusting bolt pushes on to this to lock it. At the other end is a flat pad which sits on the horseshoe. You can see on the assembled parts a little raised bit on the top of the pad which also shows which way up it needs to be to get the flat side of the bar sitting in the correct place.There are 2 springs that go over the push bar. The horseshoe has 2 bolts holding it in situ and a bit of thread lock was put on as suggested by Bryan, as he has seen these come undone before.

The outer adjuster with the locking nut

[attachimg=2]

This photo shows the tensioner in the locked position and will be adjusted when the top end is all in place and the top mark showing the push bar is facing the correct way. You can see the pad that goes onto the horseshoe.

[attachimg=3]

The casing then had the lightest smear of Honda Bond applied, also to the outer sides of the oil seals. The primary chain is in situ on the drive sprocket. There is only the primary chain holding the drive sprocket in place at this stage, hence it's funny angle as the drive shaft is inserted after the cases are put together.

[attachimg=4]





Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 14, 2017, 07:59:58 PM
The other case had bearing guard applied to the shells. No, that's not a crack across the chain guard, it's a piece of cotton from a rag !!!!

[attachimg=1]

And the cases were put together, not forgetting the dowels and bolted and torqued.

The Primary shaft was then put through the side of the casing, through the circlip, the bearing, the other circlip, through the drive sprocket hub, through the drive sprocket and the collar and through the circlip, the bearing and the other circlip and out the other side. Another collar was put over the shaft, the cog was put on the end of the shaft. Finally the Primary shaft lock washer was installed with 'OUTSIDE'.....facing outside !!!.

[attachimg=2]

You can see the new head stud in place replacing the one that had to be mullered to get out.

[attachimg=3]

You can see on the photo the kick start mechanism I installed the other day. And the advance/ retard unit has been put back on.

[attachimg=4]

[attachimg=5]


I have a couple of bolts missing from the top casing at the front. I can only think that there were Allen bolts fitted, so I will replace with the correct ones.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 14, 2017, 09:09:52 PM
NOW............the most amazing thing, the head has been skimmed. He says it was my nagging that made him do it but I think it was the promise of bacon and onion suet roly poly that encouraged him really .

The dotted lines show the most skimmed area and Trigger says this is quite common as it heats up more on #2 & #3 more than #1 & #4.

[attachimg=1]

And..........the front brake disk has been skimmed also. The front face of the disk was as flat as a witches tit, the backside was like a roller coaster. I hope all this will stop the squeak !!!!

[attachimg=2]

[attachimg=3]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 14, 2017, 09:38:44 PM
not just stop the squeal !!

  but stop the bike !! and you
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 14, 2017, 09:40:26 PM
not just stop the squeal !!

  but stop the bike !! and you
Ah,yes, that as well John ☺☺☺
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on December 15, 2017, 07:43:07 AM
I've only been away a couple of days and I when I return I find you've nearly completed the bottom half! Well done Julie, it's looking good, barrels and head on for Christmas?
Personally I love a bit of brake squeal, it wakes up the box driving morons who frequent London's clogged roads whilst on their mobiles, driving their 4x4's and oblivious to anything around them!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Greg65 on December 15, 2017, 07:54:53 AM
Julie, thank you for such an informative and detailed series of post's.  I have spent the last 18 months tinkering with my GS 1000 and now turning my attention to my 400. Your blog is really inspirational and I am currently reorganising my workshop before I put spanner to bike. Now I must return to page 6 and read the rest.

Happy bolting to one and all.

Greg
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 15, 2017, 08:38:48 AM
I am still finding the manuals very lacking. I'm using a combination of both Haynes and the proper Honda Shop manual. These manuals are OK if you have the basic mechanical knowledge needed for the job but for a complete novice numpty like myself, I have to make a lot of assumptions and use my imagination.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 15, 2017, 06:38:23 PM
Thats the problem with the Honda workshop manuals---they were written for Honda workshops!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: haynes66 on December 15, 2017, 08:22:17 PM
i also want to say how inspirational this thread has been. i have two 750-4 hondas which will be stripped and rebuilt side by side but i've been waylaid by a number of major issues which have knocked me for six since the beginning of 2016. and to be honest, i've been struggling with a lack of confidence generally, and lacking the courage to tackle the engine strip. i've stripped and rebuilt two TL125 hondas, a couple of fordson major tractors and a number of machines over the years. but for some reason i've been putting this off all the time, focusing instead on calipers and brackets etc.  but i'm determined to make a start in the new year after seeing this engine coming together. thank you, nurse!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 16, 2017, 12:42:44 PM
Agree with above posts, very well illustrated too with your photos too Julie.

Something it also illustrates,  it's often given that conventionally when you drain old oil from engines which is often sludgy,  then it contains a lot of metal that's been worn away from the inside components. Your example here ( excluding the obvious missing bits of piston)  proves really that's not the case.
At the mileage it's covered most of it is still there!
Most of the parts you've assessed still have virtually all of their original materials in place,  this view aided by your cleaning and recording of the parts with photos for us to see.

It's more the case that with oil changes completed,  then very little wear actually takes place.

It's obvious problems accepted,  it appears that this one has been looked after, service wise, right from the outset.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 16, 2017, 12:54:05 PM
I think it has been well maintained in the past Nigel and certainly has since I purchased it. We all go on about oil, what it's got in it, or hasn't got in it or how expensive or cheap it is but I still think it is the frequency that the oil is changed that is more important than the chemical make up of the oil. I will carry on with my 1000 mile oil / filter change (after the initial 500 mile running in oil change) in the hope the engine lasts longer than I do  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on December 16, 2017, 01:15:38 PM
Yes,  agree, oil condition trumps most other things in general use with these engines.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 10:03:21 AM
Re assembled the gear shift mechanism yesterday.

There are 4 parts. Only 3 show in this photo as even though I thought I had taken a pic of the gear shift spindle, I hadn't !!!
Left to right  Neutral stopper arm, Positive stopper and gear shift drum stopper.

[attachimg=1]

The gear selector drum needs to be in neutral as identified by seeing the brass point through the hole on the opposite side of the casing

[attachimg=2]

First, the neutral stopper arm is fitted, with one end of  the spring in the notch on the lever and the other end of the spring hooked on the crankcase. You can just about see the 2 ends of the spring in this photo.

[attachimg=3]

Then fit the gear shift drum stopper, once again locating the ends of the spring in the notch and the other hooked on the crankcase

[attachimg=4]

Then fit the positive stopper assembly with the two hairpins either side of the pivot post of the neutral stopper arm.

[attachimg=5]




Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 10:08:00 AM
Then the gear shift spindle was pushed through to the other side and through the new seal

[attachimg=1]

This photo shows everything in its correct place with all bolts tightened up

[attachimg=2]

Finally, all gears were found and I have marked them on the drum stopper plate

[attachimg=3]

I will tell the truth here. I couldn't remember how I took this lot apart during stripdown and I hadn't taken a photo either, which is strange as I seem to have taken photo's of the most ridiculous silly little parts. I first reassembled it, trying to remember how it all went and failed miserably. I had all the parts in the right place but it was all just sitting there and I just couldn't work out how it was meant to function or operate. I had to get Trig to have a look and, stupid me, I had not jammed the ends of the springs against the casing and therefore they were just sitting in thin air and there was no tension and nothing would work. Stupid of me really, I even kept looking at the pictures in the manual etc and reading what to do and every time I missed the line saying 'and hook their springs into the crankcase'............never mind, all sorted now.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 10:22:18 AM
And finally for yesterday a nice simple job, putting the 4 screws in the oil separation plate in the sump.........another little bit finished

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Spitfire on December 20, 2017, 12:09:05 PM
It's so satisfying sitting there with a pile of clean refurbished/new parts and put an engine back together, I used to love it, keep up the good work.

Cheers

Dennis
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 04:44:30 PM
It's so satisfying sitting there with a pile of clean refurbished/new parts and put an engine back together, I used to love it, keep up the good work.

Cheers

Dennis
Yes Dennis, it is rather nice working with all clean bits, it makes this job a lot more civilised than it could have been.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 05:38:59 PM
I lapped in the valves this afternoon. Had never done it before so had to have a Tutorial from Trig. Took me ages to do but got there in the end.



[attachimg=1][attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on December 20, 2017, 07:34:57 PM
I hate doing that job especially when the poxy rubbers won't stay stuck to the valve 😡😡
Did get a good tip that does work tried it last time, self adhesive Velcro cut to the size of the rubber and the valve👍👍👍
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on December 20, 2017, 08:11:43 PM
You could use a  small piece of fueltubing on the valve stem.to help twist.also pull the head on the seat.

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Drew400 on December 20, 2017, 08:13:35 PM
Hi Julie,

Reading your update with interest (after a long lay-off the site).

I'm a big velcro fan (for all the right reasons!) and you've just given me a new right reason. Wish I'd read that before I struggled with my sink plunger-style lapper-in tool!

Keep up the good winter work.

D.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 08:30:58 PM
I actually just did it the 'normal' way, rubber on the valve. It took me a very, very long time to get them as perfect as I could. And yes, the bloody thing kept slipping off and my hands are quite sore now. Reminded me of trying to start a fire with a stick in a hole 😁😁😁
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on December 20, 2017, 08:48:58 PM
I use some super sticky double sided tape that we used for sticking grinding stones to their face plates when i was a plating tech, you have to use a good solvent to remove it though.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 20, 2017, 09:59:10 PM
Chuck type tap wrench, attach to the other end of the valve and pull the valve against the seat rather than push it against. Works much better as you can really get a good pressure on there so speeds the job up.
It took me so long Ken I was tempted to stick the plunger on the end of my Frappe whisk and have a go with that  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 21, 2017, 09:36:50 AM
You used to be able to buy a tool that one end went in a drill chuck whilst the other had a rod with sucker and the box in the middle converted rotating motion to back and forth
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 21, 2017, 11:31:17 AM
You used to be able to buy a tool that one end went in a drill chuck whilst the other had a rod with sucker and the box in the middle converted rotating motion to back and forth
Like this you mean Bryan

[attachimg=1]

[attachimg=2]

[attachimg=3]

Trigger said why didn't I use this...... after I had spent hours lapping them in by hand  >:( >:( >:(. It was in another tool chest that I had never looked in. Fits in a pillar drill and the head sits in a stand that holds it horizontal but with the valve vertical. So, just pull the pillar drill down with this attached to it at low speed. Oh well, I will remember it for next time.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 21, 2017, 04:40:33 PM
Continued working on the head today after yesterdays lapping in. In theory and also in practice to most of you, getting the valves in is no problem I'm sure and even I was thinking here is a nice little job to do. But, gosh, did I struggle big time.

The theory..... 1) Put outer seat over valve stem. 2) Put inner seat over valve stem. 3)  Fit valve stem oil seals on the inlet valves.   4) Put smaller spring over valve stem. 5) Put larger spring over the smaller spring. 6) Place retainer on top. 7) Insert cotter valves.  8) Compress all together with the valve spring compressor.
(I have no idea where the smiley chap with the shades came from, it's supposed to be a number 8.......can't delete or change it either  ;D ;D ;D)

Well, No's 1 to 7 no problems at all. The big problem came when I was trying to use the valve spring compressor. Firstly, my hands are really very small and as you would expect, not as strong as a mans. I was struggling that much the compressor kept moving around when I was trying to compress the spring and the cotter valves kept dislodging and falling out, even though I had put grease on them to hold them in place. In the end I only managed one complete valve and that took ages and an awful lot of swearing. I had to ask Trig to do the rest for me. Utter failure on my part, most disappointed in myself.

This pic shows the valve stem oil seal in situ on the inlet valves before putting all the other bits on

[attachimg=1]

And here it is all finished. I managed the one right end of the bottom row !!!

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on December 21, 2017, 05:11:15 PM
Well done Julie, at least you tried and managed one valve, it's not easy. Fitting valve springs etc is one of those jobs where you need to use your bare feet to hold the springs in place whist one hand holds the spring compressor and the other hand fits the collets. It sounds difficult but you'll soon get the knack of it with practice and a visit to an osteopath afterwards. :o.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 21, 2017, 05:14:33 PM
Well done Julie, at least you tried and managed one valve, it's not easy. Fitting valve springs etc is one of those jobs where you need to use your bare feet to hold the springs in place whist one hand holds the spring compressor and the other hand fits the collets. It sounds difficult but you'll soon get the knack of it with practice and a visit to an osteopath afterwards. :o.
That's where I was going wrong then, I still had my socks on 😁😁😁😁😁
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on December 21, 2017, 06:01:37 PM
I have just looked at that head and wondered how Honda machined the bearing journals, naturally the cover and head are matching, i can speculate how it was done but does anyone know for sure, all of my big Kwaks have been line bored, and many of the other marques of bikes are line bored including Hondas so how were these done?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: matthewmosse on December 21, 2017, 06:03:06 PM
It is indeed a royal swine of a job. My valve compressor is a G clamp and a bit of gp100 fork with a slot cut in it. If 8ts seated just right you can put the head down on a worktop and use both hands to get the college in, but if it ain't quite right it slips off and you are searching the floor for the bits that got launched. Brings back memories of my first cb550 engine rebuild, similar head damage and pistons but all 4 equally dead. My workshop was still in early build phase so I was stood in a muddy puddle using an old sideboard as a work bench. Had to get it back running in 3 days start to finnish so no nice machined bits just whip it appart, lap the valve seats and bung in new pistons, clean out broken rings and sludge, check gearbox for debris and thrash the bike round the top of  Scotland and back. It put me right off doing head overhauls especially as engines from breakers were cheap up to fairly recently.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on December 21, 2017, 06:20:41 PM
I have been curious as to how Honda machined the head and cover journals... for 40 yrs !
Nobody seems to know for sure but there are places that can do it in the UK , I hear from other restorers.
The only way I can see that could feasibly achieve the fine finish and tolerance would be a single point cutter but the setup would be very slender. Unless they used a ball end mill and profiled each in turn?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on December 22, 2017, 08:53:21 AM
I think the machining was done on a vertical mill with a Tee shaped drive box and sized cutters plunge milled, it is after all softish alloy
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on December 22, 2017, 09:31:42 AM
About the cam journal nachining....

Think Bryan has it. Honda had to have a dedicated setup to do the quantities they produced.
A fast, cheap method using a sized cutter makes sense.

The anoraks among us would like to see some period footage showing the machining of Honda engine castings.

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 22, 2017, 05:05:00 PM
Did some more building today, nice little bits to play with and thoroughly enjoyed myself.
Put all the bits back in the rocker cover. These are the bits I started with

[attachimg=1]


[attachimg=2]


[attachimg=3]

Fitted the flywheel and took the clucth apart and gave it another clean before reassembling

[attachimg=4]

I still have to fit the clutch lifter bearing. I have one here but I ordered the wrong one, so have ordered the correct one today.

The rocker cover re assembled with the tacho drive back in, held in with a minute little circlip and new seal fitted

[attachimg=5]

Everything is all torqued up and the bottom end is now ready to go back in the frame and all the top end components are reassembled. I will refit the oil pump later today along with the neutral switch. The only thing I have not had done yet is the rebore as my pistons and rings are stuck in customs, so the rebore will be done after Christmas or early in the new year.
I must be getting somewhere because I had all the parts in 4 big Lin bins and I am now down to a very few parts in the bottom of 1 Lin bin.........getting there.


[attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on December 22, 2017, 07:22:28 PM
Did some more building today, nice little bits to play with and thoroughly enjoyed myself.
Put all the bits back in the rocker cover. These are the bits I started with

(Attachment Link)

And here is it all together

(Attachment Link)

The tacho drive, held in with a very small circlip and greased and a new seal on the outside.

(Attachment Link)

Fitted the flywheel and took the clucth apart and gave it another clean before reassembling

(Attachment Link)

I still have to fit the clutch lifter bearing. I have one here but I ordered the wrong one, so have ordered the correct one today.

(Attachment Link)

Everything is all torqued up and the bottom end is now ready to go back in the frame and all the top end components are reassembled. I will refit the oil pump later today along with the neutral switch. The only thing I have not had done yet is the rebore as my pistons and rings are stuck in customs, so the rebore will be done after Christmas or early in the new year.
I must be getting somewhere because I had all the parts in 4 big Lin bins and I am now down to a very few parts in the bottom of 1 Lin bin.........getting there.
This is really getting me in the mood for a engine build I have 2 apart and preped ready to start assembly but it's been a few years a move if house and a shit load of personal problems I really don't ķnow where all the bits are
Well done so far I have just spent 90 mins going through unread posts on this thread . You are quite lucky as in you have access to good quality tools and triggers knowledge  but I admire  that you will only use him if you really have too
Keep it up julie

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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: GiannisFour on December 23, 2017, 07:10:19 PM
Julie,
a question,what brand gaskets,o-rings and seals are you using?
Thanks
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 23, 2017, 07:20:27 PM
Julie,
a question,what brand gaskets,o-rings and seals are you using?
Thanks
Genuine Honda oil seals and this gasket set, which includes all the 'O' rings etc Giannis
Edit. I have just been reminded that the oil bung 'O' rings were not included in the Gasket set.

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: GiannisFour on December 23, 2017, 09:57:47 PM
I used the same for my 500 restoration 2 years ago,no problems so far. Yes the oil pump rings are not in the kit.
The reason i asked you, is that i want to see what is best for my future 400 restoration,probably next year.
The OEM gaskets probably is the best ,but price goes 5 or 6 times more.Don't know about VESRAH or something else.

keep up the good work on the bike!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 23, 2017, 10:05:39 PM
I couldn't find a VESRAH anywhere for this engine and I wouldn't pay the silly money for an OEM set but once again, couldn't find one anyway. I'm not precious about what make of gaskets I use on my own bikes. As long as they fit and more importantly, as long as I fit them correctly, that's good enough for me.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: GiannisFour on December 23, 2017, 10:11:47 PM
I couldn't find a VESRAH anywhere for this engine and I wouldn't pay the silly money for an OEM set but once again, couldn't find one anyway. I'm not precious about what make of gaskets I use on my own bikes. As long as they fit and more importantly, as long as I fit them correctly, that's good enough for me.

4into1 is US has the Vesrah set. About the rest  you said i agree with you  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: haynes66 on December 28, 2017, 06:05:15 PM
just been re-reading the whole thread again and i was wondering if you re-used the crankshaft shells? i've been watching the peter anderson youtube series and he is replacing pretty much everything including the shells even though they are hardly worn. he clearly has enough cash to do this but is it really necessary? obviously i intend to fit new bushes and seals throughout but if most roller bearings are good they will probably go back in. is this false economy?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 28, 2017, 07:13:16 PM
I re used all the shells that I took out of the engine. They all measured a long way within service limit and had no scores, or damage so no reason not to reuse them again. Even if money was of no object I still wouldn't have changed them, as I saw no point in changing just for the fun of it. Also, I never had any issues with those components before the pistons broke up, no knocking or rumbling from anywhere. In fact, it really is only the pistons / rings / bores that are wrecked, everything else in the engine is in excellent condition. Yes, new seals etc fitted though, along with new primary and cam chains, blades etc.
Just looked, it was page 16 I mentioned I would be reusing all the original shells. I even used the original valve guides as they had no wear at all. (Shame really as I had managed to buy NOS guides just in case but surplus to requirement now !!!!)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: haynes66 on December 28, 2017, 08:13:51 PM
thank you. that's very helpful as both my engines are low mileage so fingers crossed, i wont have to replace too much. does trigger supply gasket sets, seals, bearings etc for the 750?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 28, 2017, 08:21:53 PM
I'm sure Trig will be able to supply, just PM him nearer the time with your requirements.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: haynes66 on December 28, 2017, 08:33:15 PM
great, thanks. and i hope you both have a happy and prosperous new year.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on December 28, 2017, 08:35:36 PM
Thank you and a Happy, Healthy and productive 2018 to you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 12:02:51 PM
New pistons and rings arrived today. Re bore being done tomorrow.

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 03, 2018, 12:35:29 PM
Are you doing it Julie  ;) ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 12:48:58 PM
Are you doing it Julie  ;) ;)
Ha, not on your Nellie Paul. I am staying right away from all the machine work, that's Trigs department. I can just imagine the reaction from him if I got it wrong or messed up or broke a boring bar or whatever it's called. No, let those that know what they are doing......do it !!!

I'm getting quite excited now as this is the last of the machine work, then I can just re assemble the top end. I have already re built all the individual components for the top end so just a case of fitting the pistons/ rings and finish building up from there.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on January 03, 2018, 01:33:26 PM
Are you doing it Julie  ;) ;)
Ha, not on your Nellie Paul. I am staying right away from all the machine work, that's Trigs department. I can just imagine the reaction from him if I got it wrong or messed up or broke a boring bar or whatever it's called. No, let those that know what they are doing......do it !!!

I'm getting quite excited now as this is the last of the machine work, then I can just re assemble the top end. I have already re built all the individual components for the top end so just a case of fitting the pistons/ rings and finish building up from there.
Does trigg do rebores

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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 01:35:15 PM
Are you doing it Julie  ;) ;)
Ha, not on your Nellie Paul. I am staying right away from all the machine work, that's Trigs department. I can just imagine the reaction from him if I got it wrong or messed up or broke a boring bar or whatever it's called. No, let those that know what they are doing......do it !!!

I'm getting quite excited now as this is the last of the machine work, then I can just re assemble the top end. I have already re built all the individual components for the top end so just a case of fitting the pistons/ rings and finish building up from there.
Does trigg do rebores

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Yes Pete, he does
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on January 03, 2018, 01:37:45 PM
Are you doing it Julie  ;) ;)
Ha, not on your Nellie Paul. I am staying right away from all the machine work, that's Trigs department. I can just imagine the reaction from him if I got it wrong or messed up or broke a boring bar or whatever it's called. No, let those that know what they are doing......do it !!!

I'm getting quite excited now as this is the last of the machine work, then I can just re assemble the top end. I have already re built all the individual components for the top end so just a case of fitting the pistons/ rings and finish building up from there.
Does trigg do rebores

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Yes Pete, he does
Can you get him to pm me a price for 750 I have pistons and rings

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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 01:39:11 PM
Are you doing it Julie  ;) ;)
Ha, not on your Nellie Paul. I am staying right away from all the machine work, that's Trigs department. I can just imagine the reaction from him if I got it wrong or messed up or broke a boring bar or whatever it's called. No, let those that know what they are doing......do it !!!

I'm getting quite excited now as this is the last of the machine work, then I can just re assemble the top end. I have already re built all the individual components for the top end so just a case of fitting the pistons/ rings and finish building up from there.
Does trigg do rebores

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Yes Pete, he does
Can you get him to pm me a price for 750 I have pistons and rings

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Yes Pete, I will ask him to PM you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on January 03, 2018, 02:16:35 PM
Keep up the excellent thread. As the bores/pistons/rings are the only major replacement parts.
What does Trig advise for oil and running in etc

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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 03:30:21 PM
Keep up the excellent thread. As the bores/pistons/rings are the only major replacement parts.
What does Trig advise for oil and running in etc

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If I had my way I would take the advice of the Drag Boys and take it down the 1/4 mile absolutely screaming it's arse off  :o................................. or I could pootle around at 20 mph for the next 10 years and end up with the pistons in the same state they were in when I started  :'(.
But Trigs running in advice on this engine is 10w40 Mineral oil, ride it mid range revs, get it very hot with lots of cool air blowing around the barrels and change the oil at 500 miles.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 03, 2018, 04:03:32 PM
Good luck getting the rings in Julie if he makes it as tight a tollerance as he did mine.
Good job the 400/4 has a very generous lead in  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 04:12:42 PM
Yes Paul, the tolerance on mine will be the same as Trig did on yours.....tight. I know your engine is running as sweet as a nut since Trig did the work for you so I have no doubt mine will be the same, spot on.
Maybe my small hands and fingers will be just right for getting the rings in, I'm hoping so anyway  ???
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 03, 2018, 04:19:09 PM
Yes Paul, the tolerance on mine will be the same as Trig did on yours.....tight. I know your engine is running as sweet as a nut since Trig did the work for you so I have no doubt mine will be the same, spot on.
Maybe my small hands and fingers will be just right for getting the rings in, I'm hoping so anyway  ???

Sure is can't wait for the summer this bloody weather is a right pain in the arse :-[ :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 03, 2018, 04:27:06 PM
Yes Paul, the tolerance on mine will be the same as Trig did on yours.....tight. I know your engine is running as sweet as a nut since Trig did the work for you so I have no doubt mine will be the same, spot on.
Maybe my small hands and fingers will be just right for getting the rings in, I'm hoping so anyway  ???

Sure is can't wait for the summer this bloody weather is a right pain in the arse :-[ :'(
Agree with that Paul and I will have 2 engines to run in as the CB550 Mongrel will go on the road as well, so I need wall to wall sunshine from 1st April - 31st September  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 04, 2018, 03:57:39 PM
You had better export them to Cyprus then 8) 8)
We are looking at Northern Cyprus again this year ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 04, 2018, 04:17:54 PM
I'm thinking I may fly them out to India with me in March, guaranteed sun and warmth there  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 04, 2018, 04:51:18 PM
you on holiday AGAIN  8) 8) 8)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 04, 2018, 04:56:27 PM
you on holiday AGAIN  8) 8) 8)
Yes Paul, anooooooooother holiday  ;D ;D And before we go to India, I'm off to Slovenia for a few days with my Nursey Girlfriends. Back in UK for a couple of days then off to India, so out of the UK for most of March.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on January 04, 2018, 05:12:35 PM
Those pistons look very shiny and blingy Julie, shame to put them into the engine where they can't be seen!
I find the smaller the piston the easier they are to get into the cylinder especially with the luxury of a lead-in. The real problem is being able to insert two pistons at the same time!
I found the 250RSA piston to be a bit of a pig to insert into the bore and not helped by the stroke being so short. I couldn't get the ring compressor out once the rings were in the bore. I had to resort to the small blade screwdrivers pushing on each ring method to eventually get the piston into bore. Satisfying in the end though when you can turn the crank at the piston glides to the top of the bore.
Great thread and keep it going  :).
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 04, 2018, 05:23:19 PM
Those pistons look very shiny and blingy Julie, shame to put them into the engine where they can't be seen!
I find the smaller the piston the easier they are to get into the cylinder especially with the luxury of a lead-in. The real problem is being able to insert two pistons at the same time!
I found the 250RSA piston to be a bit of a pig to insert into the bore and not helped by the stroke being so short. I couldn't get the ring compressor out once the rings were in the bore. I had to resort to the small blade screwdrivers pushing on each ring method to eventually get the piston into bore. Satisfying in the end though when you can turn the crank at the piston glides to the top of the bore.
Great thread and keep it going  :).

Well at least the pistons look a million times better than the ones I took out !!!!. I think when I put the barrels on the pistons, I will just have to take my time and also make sure that Trig is around to help if I get stuck, or more to the point, loose my patience  ::) ::) I have seen him do it on so many Honda 4's but he usually makes it look so easy but I'm sure it's not.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on January 04, 2018, 05:33:57 PM
Just think to yourself. .. slowly, slowly,  catchee monkey and they'll go in nice and easy.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 04, 2018, 05:58:03 PM
Just think to yourself. .. slowly, slowly,  catchee monkey and they'll go in nice and easy.
I hope so Mike.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 04, 2018, 08:11:58 PM
Wide cable ties can be used to hold the new rings in their grooves if ring compressors are not available... a  bit fiddly and probably 2 ties are needed per piston.
Plenty of oil in the bores ( there may be something better out there that sticks to the cylinder walls for longer?). String and blocks to support the barrels helped too !
Worked for me and I was a newbie to the task having only ever fitted a new piston to a 2 stroke scooter !
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on January 05, 2018, 08:33:06 AM
Recently done a 1200 wing, now they are a real pain in the butt, if you get proper Jubilee clips and not cheap copies they are wider and just cover the 3 rings to make it easier
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 05, 2018, 04:47:53 PM
Fitted the new clutch lifter bearing. I had ordered the wrong one before. Even though there was nothing wrong with the clutch operation before I took the bike off the road, when I took this bearing out it and checked it, it sounded really scrunchy when moving it around so I decided to replace it. This is the only roller bearing I have changed throughout the build, the rest were fine and did not need changing.

[attachimg=1]

I also refitted the oil pump that I refurbed a few weeks ago. The oil pressure switch wire was not in a particularly good state so I made a new one and fitted it.

[attachimg=2]

And the engine is back in the frame. Unfortunately, at this stage I cannot put the front engine mounting brackets and bolts back on as I have engine crash bars fitted and the engine bolts act as the fitting points for the bars. If I fit the bars back on now, I cant get proper access to fit the side casings, ancillaries etc and it would be very close at the top when I put the barrels back on. I will fit all the side casings etc, the barrels and the rest of the top end and then bolt the engine in place with the crash bars. I have got the rear mounting bolt in place though.

[attachimg=3]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Integra99 on January 05, 2018, 05:02:20 PM

Looks fantastic... !
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 05, 2018, 11:01:13 PM
Flying together now then....

I have the same bike ramp nowadays.... a bargain when MachineMart have their VAT free offer.
Wish I had got it a few years ago when I was rebuilding the 400/4.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 06, 2018, 12:04:31 PM

Looks fantastic... !
Thank you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 06, 2018, 12:09:23 PM
Flying together now then....

I have the same bike ramp nowadays.... a bargain when MachineMart have their VAT free offer.
Wish I had got it a few years ago when I was rebuilding the 400/4.

Yes, I feel like I'm getting somewhere now. The stripping, diagnostics, cleaning, measuring, machine work and general prep seemed to have taken an age. I suppose it's still more efficient doing it that way instead of having a load of dirty bits laying around that you need to clean etc each time you want to fit something.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 06, 2018, 04:47:05 PM
Just fitting bits and pieces this weekend. Leaving the barrels / head until I have plenty of time to concentrate on the job without having to rush off somewhere.

Fitted the oil strainer and sump back on.

The strainer has very fine metal mesh.

[attachimg=1]

The other side of the strainer where the big spring fits over.

[attachimg=2]

Once fitted the spring pushes the strainer down onto the lip in the recess of the oil separation plate.

[attachimg=3]

This is where the strainer and pipe fits.

[attachimg=4]

And finally, all in place.

[attachimg=5]

New sump gasket fitted and sump bolted in place.

Truth time. I had fitted the strainer and bolted up sump and saw the spring still sitting on the work bench, silly bitch I said to myself and set about undoing all those sump bolts and fitting the spring. Not concentrating !!!!! ::) ::) ::)

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Spitfire on January 07, 2018, 12:05:22 PM

Truth time. I had fitted the strainer and bolted up sump and saw the spring still sitting on the work bench, silly bitch I said to myself and set about undoing all those sump bolts and fitting the spring. Not concentrating !!!!! ::) ::) ::)

It happens, you are feeling great, things are good and whoops how did I do that, never mind it's looking good and the photos are superb

Cheers

Dennis
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on January 07, 2018, 04:13:19 PM
If you leave most of the engine bolts out except the bottom two, you can jack the rear of the engine up as far as it will go.   That then gives an extra 20mm or so to get the carbs in.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 07, 2018, 04:46:29 PM
If you leave most of the engine bolts out except the bottom two, you can jack the rear of the engine up as far as it will go.   That then gives an extra 20mm or so to get the carbs in.
Thanks Mike, that's worth bearing in mind. I usually don't have a problem fitting the carbs back on, I just push and compress the airbox back as far as it will go and then start wiggling them in. As always, it's not the easiest job in the world but I  usually manage.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 08, 2018, 05:43:18 PM
Still finding myself short on time at the moment, but continuing with little bits of work.

Took apart this part of the clutch mechanism today to give it a good clean.

[attachimg=1]

On the back side it was full of old gritty, dirty grease and I'm sure not performing to it's best, although I never felt there was anything wrong with it.

[attachimg=2]

[attachimg=3]

Looks a lot better after a good clean. I will re grease everything and re assemble and fit the casing to the bike.

[attachimg=4]







Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 08, 2018, 05:49:15 PM
Fitted the front sprocket

[attachimg=1]

Cleaned the alternator up a bit and fitted it to the bike.

[attachimg=2]

And fitted the starter motor. You can see through the hole where the spline locates on the gear.

[attachimg=3]

[attachimg=4]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 08, 2018, 07:14:25 PM
Julie

Is that a new O ring on the starter motor spigot?
I doubt they ever leak ? .... just looks a bit flat in its groove.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 08, 2018, 07:55:08 PM
Julie

Is that a new O ring on the starter motor spigot?
I doubt they ever leak ? .... just looks a bit flat in its groove.
I think it's my dodgy photo Clem, it is a new one, it is just sitting proud, not by much..... but just.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 08, 2018, 08:16:52 PM
I was paranoid about all the seals being renewed when I rebuilt mine....no leaks to date.

Now I just want it running right....  I suspect the cylinder head work that I offloaded, through lack of  confidence in my skills,  might not have been done quite thoroughly enough. This year's challenge.

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 08, 2018, 08:44:16 PM
I was paranoid about all the seals being renewed when I rebuilt mine....no leaks to date.

Now I just want it running right....  I suspect the cylinder head work that I offloaded, through lack of  confidence in my skills,  might not have been done quite thoroughly enough. This year's challenge.
I'm finding it's not difficult to get paranoid when building an engine and I'm definitely not the paranoid type!!!.
I will have replaced all the seals, O rings etc on this build, no point in not replacing them in my mind. Thinking that all the rubber bits are almost 40 years old, except the gear change lever seal that I changed last year, they are all due for a change.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 11, 2018, 06:50:10 PM
Just a tantalising glimpse....full update tomorrow  ;D ;D ;D

[attachimg=1]

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 12, 2018, 08:13:04 AM
WHOOOoooo ;D ;D Looking good
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Integra99 on January 12, 2018, 08:16:59 AM

Nice work... looking lovely! on the homebound stretch now!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: taysidedragon on January 12, 2018, 11:25:13 AM
Looking good. There might be a problem with that camshaft though!  ;) :o
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 05:50:16 PM
Looking good. There might be a problem with that camshaft though!  ;) :o
Yep, it will never work  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 05:54:04 PM
Going back 2 days.

The barrels have been rebored to +.50. The rebore was done to a physical piston and the barrels were cross hatched. The tolerance is about 1 thou.
I fitted the rings to the pistons. The bottom ring or oil ring has 3 parts to it. With these 3 parts you fit the spacer ring on the piston first and then 1 rail on top and one underneath making a spacer sandwich. The second ring goes in the middle groove of the piston and has a very square cut face to it. The top ring has a little sort of chamfer on the top and bottom edge.  Any markings on the second and top rings have to face upwards. Luckily, Trig just happened to pick up one of the pistons and although I thought I had checked to make sure I put the rings in with the writing facing upwards, there was one top ring facing downwards……how pleased am I that he noticed my cock up.
All the rings were staggered around the pistons at approx. 120°.
The circlip was then fitted to the farthest side of the pistons from the side I was working and the pistons put on top of the con rods with the arrow on the piston facing the front of the engine and ‘IN’ facing the rear and the gudgeon pin pushed through from my side. Then the other circlip was inserted with the little tail pointing downwards. I actually found the circlips quite difficult to get in, not because they were particularly tight but I just couldn’t seem to get the angle right with the thin nose pliers so I got Trig to do them for me as I was worried about bending them out of shape.

I put the dowels in and as these dowels have oil coming up through them, Trig said that he always fits an ‘O’ ring around the dowel, just in case. This ‘O’ ring is not mentioned anywhere in the service manual and does not come in the gasket set. Trig punched out the hole in the gasket just a little larger to accommodate the seal. I then fitted the gasket, trying it both ways round to make sure I had ‘the best fit’. In fact this pattern gasket set has been very good for sizes, shape, holes in the exact right place etc. I then dropped in the cam blades making sure they located correctly.


The 3 part oil rings

[attachimg=1]

The top ring

[attachimg=2]

The second ring

[attachimg=3]

Big 'O'rings around the bottom of the barrels

[attachimg=4]

The extra 'O' ring Trig fitted

[attachimg=5]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 06:00:44 PM
The gasket and the pistons fitted to the con rods

[attachimg=1]

The positioning of the circlip holding the gudgeon pin in situ

[attachimg=2]

We then fitted the barrels over the pistons. I was quite concerned about this and was not even going to try and do it without Trig helping me. It was actually very straight forward. We lowered the barrels down over the studs to just resting very gently on the top rings, we compressed the top rings using our fingers and by just applying gentle pressure, the barrels slipped over a treat. We did the same with the second rings and then the same with the bottom oil control rings. Once all the pistons were in the barrels, it was just a case of smacking the barrels down with your hand until they sat on top of the bottom casing.

The pistons / bores then had a good squirt of oil applied and we manually turned the engine over quite a few times to get lubrication down the side of the pistons. Then some Graphogen was applied and again, the engine turned over manually to get the pistons moving up and down.


[attachimg=3]

I then put in the oil jets with their new seals and the stud dowels with their new stud gaskets.

The oil restrictor jet and stud dowel with gasket.

[attachimg=4]

[attachimg=5]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 06:04:38 PM
Whilst assembling the engine, any dowel that has oil going up it, especially the stud dowels, was thoroughly cleaned again with a small brush to make sure they hadn't picked up any contamination.

[attachimg=5]

One thing I would mention here is that although it is easier re assembling the top end of the engine with the bottom end in the frame, I did find other bits, like frame, wiring, coils, cables etc getting in the way at times. I think if it were at all possible, I would have found the whole process much easier with the engine out of the frame. But then, you have to get the whole engine back in the frame. Not a problem if you have the bike stripped 100% as you can lay it on it’s side and do it.

 I then fitted the cylinder head gasket and the cylinder head which I had re assembled previously. I used the new Dowty washers under the special 8mm nuts and the original copper covered steel washers under the 8mm cap nuts. The head was then torqued down in sequence and left for 24 hours before re torquing again in sequence the next day.

Head bolts

[attachimg=1]

Whilst all this had been going on the cam chain had been held aloft on a piece of wire and fed through to the top.
I fitted the points plate with everything still attached from before but Trig pointed out that the covering and indeed the wire from the points had seen better days so I removed it and he un soldered the flags and soldered them back on to some new wire, I fitted a new white covering on it and put the bullets on and I must admit it looks a lot better. I refitted the points plate and found TDC 1.4 . I then fitted the cam sprocket on the camshaft and inserted in from the right of the engine and lined up the marks on the sprocket with the upper surface of the cylinder head. Now here’s a strange thing, nowhere in the Shop Manual or Haynes did it tell me which way up to have the camshaft, ie lobes facing up or down, I had to look at videos on line to in which position the lobes needed to be facing, bloody weird, unless I missed something obvious. Also, I seem to have got a ‘plate’ on the sprocket, where the two bolts go through, which does not show on any fiche or in any books, so I don’t know what that is all about either. The cam chain fitted over to sprocket with no problem at all and we then undid the cam chain adjuster, which had been in the locked position with no tension, and the little bit of slack came out of the cam chain and we locked the adjust again. We turned the engine manually again, to make sure everything was turning and going up and down as it was meant to be, just for my piece of mind really.

Points and wiring before

[attachimg=2]

And after a quick refurb

[attachimg=3]

You can just see the lines on the cam sprocket in line with the upper surface of the cylinder head and the strange metal plate that seems to not be shown in any books or on any fiche

[attachimg=4]




Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 06:11:34 PM
Elastic bands were fitted to hold the tappets and rockers up out of the way whilst fitting the rocker cover to the engine. One thing I had not noticed previously was that one of the tappets had a small chip and one had quite bad pitting, so I found some replacements in the workshop and fitted them. Trig then applied a little Graphogen to the rocker pads.
I fitted the cam shaft oil spray pipes with their nice new grommets and fitted the rocker cover and bolted it all down and removed the elastic bands.
I adjusted one of the tappets and Trig did the rest. He re checked them all again this morning. This is where I found it all very awkward with the engine in the frame as it really was awkward getting the feeler gauge in the tappets with everything else in the way.

Pitted tappet

[attachimg=1]

Elastic bands holding tappets and rockers up out of the way

[attachimg=2]

A dab of Graphogen on the rocker pads



[attachimg=3]


And this is the stage that I am at now. Engine all bolted in now with crash bars fitted. Exhaust system back on. Drive chain on plus a few other bits fitted.




[attachimg=4]



[attachimg=5]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on January 13, 2018, 06:28:35 PM
Elastic bands were fitted to hold the tappets and rockers up out of the way whilst fitting the rocker cover to the engine. One thing I had not noticed previously was that one of the tappets had a small chip and one had quite bad pitting, so I found some replacements in the workshop and fitted them. Trig then applied a little Graphogen to the rocker pads.
I fitted the cam shaft oil spray pipes with their nice new grommets and fitted the rocker cover and bolted it all down and removed the elastic bands.
I adjusted one of the tappets and Trig did the rest. He re checked them all again this morning. This is where I found it all very awkward with the engine in the frame as it really was awkward getting the feeler gauge in the tappets with everything else in the way.

Pitted tappet

(Attachment Link)

(Attachment Link)

(Attachment Link)
Doing great. Not long to go
Just all the fiddly jobs looking forward to the start up

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on January 13, 2018, 06:45:13 PM
Very good clear pictures of the build Julie, getting close to firing it now.

The camshaft positioning (up or down lobes) is not important. With the crank set at T for cylinders 1 and 4, both of these are at tdc. Camshaft one way will give firing on one cylinder and exhaust on the other,  then flip the cam 180 degrees without moving the crank, and the sequence just flips cylinders with it. As they are both sparked at the same point it makes no difference which way you build it.

Nigel.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rob62 on January 13, 2018, 09:43:18 PM
Its all looking very 👍 roll on spring  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Moorey on January 13, 2018, 10:08:54 PM
Did you have to gap the piston rings at all.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on January 13, 2018, 10:30:41 PM
As Nigel said;  the camshaft position is unimportant.  This is because of the 2:1 ratio, the camshaft rotates half the speed of the crankshaft.   Think of the sizes of the sprockets - the camshaft one is bigger.
Enjoying your thread,  I like the way you're checking and refurbing everything including the points wiring.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 13, 2018, 11:26:29 PM
Did you have to gap the piston rings at all.
No gaping needed. Bored out to .50, fitted .50 rings to .50 pistons so everything fitted perfectly.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: JamesH on January 13, 2018, 11:42:46 PM
That’s looking awesome Julie. Superb job - you should be proud.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 14, 2018, 09:23:27 AM
Great job Julie ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: GiannisFour on January 14, 2018, 10:10:33 AM
Brilliant work Julie!
Thanks for sharing!  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: kevski on January 14, 2018, 03:13:31 PM
This is coming along really nicely, i guess you are itching to get the bike back on the road to harvest the fruits of your labour, i know i have when i doing this sort of work.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 14, 2018, 03:22:28 PM
This is coming along really nicely, i guess you are itching to get the bike back on the road to harvest the fruits of your labour, i know i have when i doing this sort of work.

Yes, I want it all finished ASAP but still got quite a bit to do really just fitting all the bits back on. I'm on the homeward stretch though and as far as the engine is concerned basically it's all done which is a huge relief to me. It all came together really quickly in the end, it's just all the work leading up to the re assembly that takes time. I keep wanting to go and turn the engine over manually just to make sure it all still works as it should but that's my lack of confidence in what I have done that's causing that I think.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on January 14, 2018, 03:40:28 PM
Looking good Julie. Good couple of tips with the elastic bands and the extra O ring on the dowels.
Do you know the make of the engine bars?? I bought a new set for my 400 from DS but they are the 'half cut tube' type and a reservoir for water to sit and rust. I'd like a full tube set if possible.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 14, 2018, 03:47:25 PM
Looking good Julie. Good couple of tips with the elastic bands and the extra O ring on the dowels.
Do you know the make of the engine bars?? I bought a new set for my 400 from DS but they are the 'half cut tube' type and a reservoir for water to sit and rust. I'd like a full tube set if possible.
They are Rickman's. Strange as we were only looking at some on Tinternet the other day whilst looking for something totally different and IIRC they are about £250.00
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on January 14, 2018, 04:02:23 PM
 :o! Should that be £25 Julie? S/H previously enjoyed on ebay or brand new?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 14, 2018, 04:07:12 PM
:o! Should that be £25 Julie? S/H previously enjoyed on ebay or brand new?

 ;D ;D ;D Unfortunately not £25 but £250 but that is for new ones. I have just found some on teabay USA whilst looking for something else and they are $270 which is approx. £200 so I'm sue if you really looked around you could find them cheaper. They are very good quality though and luckily mine were fitted to the bike when I got her.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on January 14, 2018, 04:15:54 PM
As i remember it if you bought Honastyle I.E. genuine Honda they were made by Rickman, same as the fairings
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: SteveD CB500K0 on January 14, 2018, 05:07:47 PM
I had them too (avatar).
Same with the Hondastyle fairing which was a Rickman type 2.


Sent from my iPhone using Tapatalk
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 05:43:32 PM
The engine is now all complete and the bike is back together, all but the carbs. I wanted to get the carbs fitted and fire her up as I am an impatient bitch but Trig said........ NO !!!. He wants me to wait so the first time I fire her up I can take her for a very long ride ie, 100 miles to start running her in. Now, I am a fair weather rider these days and just the thought of getting out on a bike this time of year for a couple of hours fills me with dread (and covers me in goose pimples !!!!). Therefore, as it's going to be some time before the first start up / ride of the year, I'm going to strip the carbs and give them a good clean, have all the necessary parts zinc plated, fit a new 'O' rings etc. Luckily, I have had these carbs apart a few times before and I know they function well just by being bench synced so will be no problem when I re fit them.

This engine strip and rebuild has been a MASSIVE learning curve for me. I knew my knowledge base was extremely limited when it comes to all things mechanical and engineering but I have always to be able to do basic routine maintenance on bikes and I though this would help but it was of no use to me at all.

It was my plan to do everything myself (except the machine work) and I suppose I did an awful lot of it but I had to keep asking questions like 'how do I do this?' or 'where does this go?' or 'why have I got this bit left over?', 'what tool do I use for this bit' and my favourite was 'no, your going to have to explain it again'. I just did not know enough of basic engineering / mechanics to do this job entirely alone. Using the Workshop Manual, the Haynes Manual and microfiches basically tells you diddly squat, they are books printed for people who know the basics of building an engine and no more.

I have learnt that building an engine is all about measurements, tolerances and individual components working together to perform a function, checking at every stage that something you have just re assembled actually works before you go on to the next component. I have also learnt that if you do it right, you do it once.

I was lucky this was a CB400/4 engine. They are compact, every component fits together really nicely and I can now understand why Ian (Orcadian) says they are like a Swiss watch, they are lovely to work on, everything is a manageable weight and size and feels 'just right'.

Would I do it again? Yes, of course I would if it were a CB400/4 engine. I feel I have learnt enough and gained an understanding of the basics of building a CB400/4 engine that I would probably enjoy it more next time.

More importantly, the damage this engine had sustained and ultimately the reason I did this strip and rebuild has been dealt with.
I have no doubts now that she will run and perform very well once run in and hopefully will be good for many more years.

Not only have I learnt the basics of the practical side of engine building but you guys have been so brilliant sharing your years of knowledge in the diagnostics of the initial problem and sharing your practical experiences, that to me has been totally invaluable. Thank you all so much for your input throughout, it has made it so interesting for me. And thanks for all the 'SOHC Banter' as well, I love it and it makes a job much nicer having a laugh. Thanks to all those that have sent me PM's, emails and texts as well, your encouragement has meant a lot to me.

Could I have done this without Trig, NO, most definitely not. I would probably still be trying to get the mullered nut off the head stud and getting nowhere fast. His theoretical knowledge and more importantly his practical experiences of engineering, engines and in particularly Honda SOHC engines never fails to amaze me. I know he is sick to the back teeth of me keeping on asking questions, wanting to queue jump for machine work and being in his workshops with all the tools out of the chests.

I will let you know when she is going on her first post rebuild run and let you know how it all goes.

Julie
 :-* :-* :-*

[attachimg=1]

[attachimg=2]

[attachimg=3]

[attachimg=4]









Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on January 17, 2018, 05:55:09 PM
Looking good girly, make sure you get someone videoing you on the first startup (NO CHEATING!, by that I mean don't have it running the day before making the video!) and then watch you ride of happy and proud. Well done sticking with it and not losing your temper and "sort it next summer/year/ decade"  like a few I've seen (and bought from people) over the years.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on January 17, 2018, 05:55:39 PM
Oh wow that looks great I am so impressed with you and your work, you have done a fantastic job
I agree with you about not wanting to ride this time of year , I ride every week all through the year but I never ride my classics when there is any road salt of wet I have  a winter hack for that
Once again well done on getting to this stage , I look forward to the start up and ride

Sent from my SM-G930F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on January 17, 2018, 06:00:09 PM
The engine is now all complete and the bike is back together, all but the carbs. I wanted to get the carbs fitted and fire her up as I am an impatient bitch but Trig said........ NO !!!. He wants me to wait so the first time I fire her up I can take her for a very long ride ie, 100 miles to start running her in. Now, I am a fair weather rider these days and just the thought of getting out on a bike this time of year for a couple of hours fills me with dread (and covers me in goose pimples !!!!). Therefore, as it's going to be some time before the first start up / ride of the year, I'm going to strip the carbs and give them a good clean, have all the necessary parts zinc plated, fit a new 'O' rings etc. Luckily, I have had these carbs apart a few times before and I know they function well just by being bench synced so will be no problem when I re fit them.

This engine strip and rebuild has been a MASSIVE learning curve for me. I knew my knowledge base was extremely limited when it comes to all things mechanical and engineering but I have always to be able to do basic routine maintenance on bikes and I though this would help but it was of no use to me at all.

It was my plan to do everything myself (except the machine work) and I suppose I did an awful lot of it but I had to keep asking questions like how 'do I do this?' or 'where does this go?' or 'why have I got this bit left over?', 'what tool do I use for this bit' and my favourite was 'no, your going to have to explain it again'. I just did not know enough of basic engineering / mechanics to do this job entirely alone. Using the Workshop Manual, the Haynes Manual and microfiches basically tells you diddly squat, they are books printed for people who know the basics of building an engine and no more.

I have learnt that building an engine is all about measurements, tolerances and individual components working together to perform a function, checking at every stage that something you have just re assembled actually works before you go on to the next component. I have also learnt that if you do it right, you do it once.

I was lucky this was a CB400/4 engine. They are compact, every component fits together really nicely and I can now understand why Ian (Orcadian) says they are like a Swiss watch, they are lovely to work on, everything is a manageable weight and size and feels 'just right'.

Would I do it again? Yes, of course I would if it were a CB400/4 engine. I feel I have learnt enough and gained an understanding of the basics of building a CB400/4 engine that I would probably enjoy it more next time.

More importantly, the damage this engine had sustained and ultimately the reason I did this strip and rebuild has been dealt with.
I have no doubts now that she will run and perform very well once run in and hopefully will be good for many more years.

Not only have I learnt the basics of the practical side of engine building but you guys have been so brilliant sharing your years of knowledge in the diagnostics of the initial problem and sharing your practical experiences, that to me has been totally invaluable. Thank you all so much for your input throughout, it has made it so interesting for me. And thanks for all the 'SOHC Banter' as well, I love it and it makes a job much nicer having a laugh. Thanks to all those that have sent me PM's, emails and texts as well, your encouragement has meant a lot to me.

Could I have done this without Trig, NO, most definitely not. I would probably still be trying to get the mullered nut off the head stud and getting nowhere fast. His theoretical knowledge and more importantly his practical experiences of engineering, engines and in particularly Honda SOHC engines never fails to amaze me. I know he is sick to the back teeth of me keeping on asking questions, wanting to queue jump for machine work and being in his workshops with all the tools out of the chests.

I will let you know when she is going on her first post rebuild run and let you know how it all goes.

Julie
 :-* :-* :-*

(Attachment Link)

(Attachment Link)

(Attachment Link)

(Attachment Link)
Thank you Julie. It has been very enjoyable and informative. Could I suggest you fill it with your oil of choice just incase you forget and try to start it !!
Best wishes for a wonderful first ride

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 06:02:51 PM
Looking good girly, make sure you get someone videoing you on the first startup (NO CHEATING!, by that I mean don't have it running the day before making the video!) and then watch you ride of happy and proud. Well done sticking with it and not losing your temper and "sort it next summer/year/ decade"  like a few I've seen (and bought from people) over the years.
Thanks Mr Hairy.I will get Trig to Video the start up and ride away. I will start giving him lessons now on how to use the Vid function on his phone, it may take some time !!!! ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 06:03:35 PM
Oh wow that looks great I am so impressed with you and your work, you have done a fantastic job
I agree with you about not wanting to ride this time of year , I ride every week all through the year but I never ride my classics when there is any road salt of wet I have  a winter hack for that
Once again well done on getting to this stage , I look forward to the start up and ride

Sent from my SM-G930F using Tapatalk
Thanks Pete
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 06:05:13 PM
The engine is now all complete and the bike is back together, all but the carbs. I wanted to get the carbs fitted and fire her up as I am an impatient bitch but Trig said........ NO !!!. He wants me to wait so the first time I fire her up I can take her for a very long ride ie, 100 miles to start running her in. Now, I am a fair weather rider these days and just the thought of getting out on a bike this time of year for a couple of hours fills me with dread (and covers me in goose pimples !!!!). Therefore, as it's going to be some time before the first start up / ride of the year, I'm going to strip the carbs and give them a good clean, have all the necessary parts zinc plated, fit a new 'O' rings etc. Luckily, I have had these carbs apart a few times before and I know they function well just by being bench synced so will be no problem when I re fit them.

This engine strip and rebuild has been a MASSIVE learning curve for me. I knew my knowledge base was extremely limited when it comes to all things mechanical and engineering but I have always to be able to do basic routine maintenance on bikes and I though this would help but it was of no use to me at all.

It was my plan to do everything myself (except the machine work) and I suppose I did an awful lot of it but I had to keep asking questions like how 'do I do this?' or 'where does this go?' or 'why have I got this bit left over?', 'what tool do I use for this bit' and my favourite was 'no, your going to have to explain it again'. I just did not know enough of basic engineering / mechanics to do this job entirely alone. Using the Workshop Manual, the Haynes Manual and microfiches basically tells you diddly squat, they are books printed for people who know the basics of building an engine and no more.

I have learnt that building an engine is all about measurements, tolerances and individual components working together to perform a function, checking at every stage that something you have just re assembled actually works before you go on to the next component. I have also learnt that if you do it right, you do it once.

I was lucky this was a CB400/4 engine. They are compact, every component fits together really nicely and I can now understand why Ian (Orcadian) says they are like a Swiss watch, they are lovely to work on, everything is a manageable weight and size and feels 'just right'.

Would I do it again? Yes, of course I would if it were a CB400/4 engine. I feel I have learnt enough and gained an understanding of the basics of building a CB400/4 engine that I would probably enjoy it more next time.

More importantly, the damage this engine had sustained and ultimately the reason I did this strip and rebuild has been dealt with.
I have no doubts now that she will run and perform very well once run in and hopefully will be good for many more years.

Not only have I learnt the basics of the practical side of engine building but you guys have been so brilliant sharing your years of knowledge in the diagnostics of the initial problem and sharing your practical experiences, that to me has been totally invaluable. Thank you all so much for your input throughout, it has made it so interesting for me. And thanks for all the 'SOHC Banter' as well, I love it and it makes a job much nicer having a laugh. Thanks to all those that have sent me PM's, emails and texts as well, your encouragement has meant a lot to me.

Could I have done this without Trig, NO, most definitely not. I would probably still be trying to get the mullered nut off the head stud and getting nowhere fast. His theoretical knowledge and more importantly his practical experiences of engineering, engines and in particularly Honda SOHC engines never fails to amaze me. I know he is sick to the back teeth of me keeping on asking questions, wanting to queue jump for machine work and being in his workshops with all the tools out of the chests.

I will let you know when she is going on her first post rebuild run and let you know how it all goes.

Julie
 :-* :-* :-*

(Attachment Link)

(Attachment Link)

(Attachment Link)

(Attachment Link)
Thank you Julie. It has been very enjoyable and informative. Could I suggest you fill it with your oil of choice just incase you forget and try to start it !!
Best wishes for a wonderful first ride

Thank you John. Oh yes, I haven't put any oil in it yet.............I knew there was something I  ::) ::) ::)had forgotten

Sent from my SM-G361F using Tapatalk
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: haynes66 on January 17, 2018, 06:08:35 PM
as above.  this thread has been really enjoyable to follow, and given me the confidence and inspiration to get on with mine. thank you both.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 06:10:00 PM
as above.  this thread has been really enjoyable to follow, and given me the confidence and inspiration to get on with mine. thank you both.
Thank you......now get spannering  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 17, 2018, 07:05:33 PM
Looks very tidy indeed.
Hope it fires up on all four at the first button press and sounds super quiet !.... should do after all that work and sweat.

Seeing the pics, I remembered that I also polished the outer cases on my original bike once the lacquer had gone west. Well, some old hand bench polisher at RR did it for me anyway.

Forgive me (Aero engine background so a proper fussy git) but I couldn't help but notice the clutch cable routing with that round guide clip fixed high up on the coil mounting...Could be a good idea but it may put the cable in a sharper bend and make the clutch action harder?  I think Honda clipped it under one of the cam cover bolts to give a bigger arc as it were. You could always experiment to see if it makes much difference at the lever?

Well done !
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 07:12:51 PM
Well noticed Clem. I remember a discussion on the forum going back yonks ago about the guide clip. By what I can vaguely remember the early 400's had it clipped under one of the cam cover bolts and the later models, mine is a very, very late model,  had the clip high up. I may experiment as this is where the clip has always been on mine but never had heavy clutch lever. Thanks for pointing it out.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Clem2112 on January 17, 2018, 07:27:43 PM
I must be noticing more detail in things at the moment.....
been tiling some walls and wishing I was better at it !

Suitably inspired so my Honda will be next .... to get those valves looked at , once have I cleansed the garage bench of all the Matchless bits and boxed them up for a while.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on January 17, 2018, 07:43:36 PM
I agree, wait for a decent monsoon to wash the dreaded salt away and for it to dry up again before taking such a tasty looking engine on the road.   Take some spanners with you in case something needs a minor adjustment, such as the gear lever position.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 07:48:08 PM
I agree, wait for a decent monsoon to wash the dreaded salt away and for it to dry up again before taking such a tasty looking engine on the road.   Take some spanners with you in case something needs a minor adjustment, such as the gear lever position.
Good idea Mike, I will take some spanners with me. I have got to the stage now where I only pick up two spanners or sockets of the wrong size before I get the one I need, so I will only have to take about 20 with me  ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on January 17, 2018, 09:30:06 PM
Looking good girly, make sure you get someone videoing you on the first startup (NO CHEATING!, by that I mean don't have it running the day before making the video!) and then watch you ride of happy and proud. Well done sticking with it and not losing your temper and "sort it next summer/year/ decade"  like a few I've seen (and bought from people) over the years.
Thanks Mr Hairy.I will get Trig to Video the start up and ride away. I will start giving him lessons now on how to use the Vid function on his phone, it may take some time !!!! ;D ;D
Jesus is he ready for video on a phone I thought he had only just managed to ring out and text😀😀
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 17, 2018, 09:37:49 PM
Looking good girly, make sure you get someone videoing you on the first startup (NO CHEATING!, by that I mean don't have it running the day before making the video!) and then watch you ride of happy and proud. Well done sticking with it and not losing your temper and "sort it next summer/year/ decade"  like a few I've seen (and bought from people) over the years.
Thanks Mr Hairy.I will get Trig to Video the start up and ride away. I will start giving him lessons now on how to use the Vid function on his phone, it may take some time !!!! ;D ;D
Jesus is he ready for video on a phone I thought he had only just managed to ring out and text😀😀


As you know Paul, Trig is a total Ludite but I will teach him how to do videos............God help us all  ::) ::) ::)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: taysidedragon on January 17, 2018, 11:52:09 PM
Well done Julie. Great work. This thread has and will be a great resource for us 400/4 'novices'.  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Bryanj on January 18, 2018, 08:05:19 AM
Having met the pair of you I had no doubt it would get done right and pretty but you have done it quick as well. Well done and enjoy it. Yes with all the bits to hand i can do a 500 in 1/2 a day or less, but not with all the polishing and painting---do a 500/550 next they are very very similar and not much heavier
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on January 18, 2018, 08:11:37 AM
Julie, I always knew nurses were under valued and under paid, now I'm in no doubt!

What an absolulutely brilliant job you have done and with such detailed posts accompanying,  making such a complex job so clear for others and giving us the confidence to take on our challenges.

One last point, this is obviously a well watched post and commented on by many different members. Is it the longest in this forum's history at 27 pages and counting?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: SteveD CB500K0 on January 18, 2018, 11:25:41 AM
Not quite on the replies but miles to go on "read"

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Moorey on January 18, 2018, 11:32:18 AM
Well done you. Give yourself a big pat on the back. Both for the job and the thread.  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on January 18, 2018, 12:03:34 PM
Not quite on the replies but miles to go on "read"

(Attachment Link)
Knew you would be there with the stats Steve!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Seabeowner on January 18, 2018, 12:58:49 PM
I’ll add to the stats. Normally don’t comment on 400s, but this is an exception as this has been such a detailed and also brilliantly photographed rebuild. Great work. It will be really a new experience riding now as you have had your hands over all its internals!  Soo much better than the poorly described and grainy b&w  pics in many manuals.  Really interesting to see how radically different the 350/400 is from 500 range.
Now do you still have that 550?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 03:48:49 PM
Well done Julie. Great work. This thread has and will be a great resource for us 400/4 'novices'.  :)
Thank you. I would still consider myself a novice but one that knows just a bit more than when I started  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 03:51:57 PM
Having met the pair of you I had no doubt it would get done right and pretty but you have done it quick as well. Well done and enjoy it. Yes with all the bits to hand i can do a 500 in 1/2 a day or less, but not with all the polishing and painting---do a 500/550 next they are very very similar and not much heavier
Thanks Bryan. I most certainly will enjoy it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 03:53:48 PM
Julie, I always knew nurses were under valued and under paid, now I'm in no doubt!

What an absolulutely brilliant job you have done and with such detailed posts accompanying,  making such a complex job so clear for others and giving us the confidence to take on our challenges.

Thanks Tim. All you need to do now is follow my pictures and your engine will be done before you know it  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 03:55:42 PM
Well done you. Give yourself a big pat on the back. Both for the job and the thread.  ;)
Thank you. I really enjoyed doing the thread, it made the build more interesting sharing it with others.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 04:28:15 PM
I’ll add to the stats. Normally don’t comment on 400s, but this is an exception as this has been such a detailed and also brilliantly photographed rebuild. Great work. It will be really a new experience riding now as you have had your hands over all its internals!  Soo much better than the poorly described and grainy b&w  pics in many manuals.  Really interesting to see how radically different the 350/400 is from 500 range.
Now do you still have that 550?

Thanks Phil. I never actually set out to produce a fully documented, photographed process map of the strip /build. As I said at the beginning of the thread it was my plan to only provide updates and pictures thinking that someone somewhere in the future may just be doing the same thing, get stuck and maybe something I had written or taken a picture of would help them out. Maybe I should ©copyright it  ;D ;D ;D. I think I also said that I would not be offended if no one commented on my posts as most of you are so experienced at this sort of thing, I assumed it would be at a too basic level to be of interest.

Now I have had my hands over the internals it has given me a huge insight as to how these engines function and a much greater understanding of how each component works. Prior to this it was a simple case of start engine, pull clutch lever in, use gear lever to change gear, throttle to accelerate and brake to stop. Now I can visualise what each part is doing inside and how all the parts, although independent, have to work together to get from A to B.

Yes, I do still have the CB550, that is my Brat style Mongrel (Now named Millie  ::) ::) ::)) that Graham has built for me. Unfortunately, he has already done a complete overhaul on the engine for me, so I'm too late on that one. I do fancy buying a CB500 for myself to ride and keep, so that may need an engine overhaul and I would have a go at that. Other than that, I have my CB750 K2, which is going to have a bit of a restoration and engine overhaul maybe later this year but, the engines on them are so agricultural and heavy, I don't know if I could do it. (I won't tell you how many of them I see in a month to be able to make that statement!!!)

I will just have to wait and see if another old Honda CB engine pops up that I fancy a go at, I will let you know.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hondarc166 on January 18, 2018, 04:40:58 PM
Nice work Julie looking good. nice to have someone like trig on hand to ask. :) :) :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: MrDavo on January 18, 2018, 05:01:13 PM
Now I have had my hands over the internals it has given me a huge insight as to how these engines function and a much greater understanding of how each component works.

I have a theory that if you understand how it works, you can fix most things yourself.

Quote
Soo much better than the poorly described and grainy b&w  pics in many manuals.

And the grainy photos taken by certain professional engine builders.

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on January 18, 2018, 05:38:24 PM
For your next project, how about a BMW K75?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on January 18, 2018, 06:43:35 PM
Julie, I always knew nurses were under valued and under paid, now I'm in no doubt!

What an absolulutely brilliant job you have done and with such detailed posts accompanying,  making such a complex job so clear for others and giving us the confidence to take on our challenges.

Thanks Tim. All you need to do now is follow my pictures and your engine will be done before you know it  ;D ;D ;D

Simples  :-\
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 06:51:38 PM
For your next project, how about a BMW K75?
Never, ever ridden a BMW bike Mike, let alone studied the engine closely.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 06:57:47 PM
Fancy another 400 I have two engines and £50 in my wallet  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 07:09:35 PM
Fancy another 400 I have two engines and £50 in my wallet  ;D

£50, bog off, it's going to cost me more than that for a manicure and nail polish  :D :D :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 07:15:25 PM
Ok £60 and all the nail polish you will ever need.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on January 18, 2018, 07:37:11 PM
Fancy another 400 I have two engines and £50 in my wallet  ;D

£50, bog off, it's going to cost me more than that for a manicure and nail polish  :D :D :D
I thought he was offering you the two engines AND the £50 to take them off his hands!!!

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 07:50:28 PM
Fancy another 400 I have two engines and £50 in my wallet  ;D

£50, bog off, it's going to cost me more than that for a manicure and nail polish  :D :D :D
I thought he was offering you the two engines AND the £50 to take them off his hands!!!

Sent from my X6pro using Tapatalk

I was slow off the mark there Hairy, in fact I now read it that he is offering me a CB400, two engines and 50 quid.......I will take the lot  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on January 18, 2018, 07:53:44 PM
You could try beating him down to 99p per motor, Trig would be so proud of you, got to be worth a try, as he's used to losing money hand over fist, he buys shitalian bikes!

Sent from my X6pro using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: tom400f on January 18, 2018, 08:01:51 PM
Best thread ever! Well done Julie and congrats to both of you.

Is your exhaust original? I know you said you have a Brituro silencer - what about the downpipes?

Super job.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 08:04:18 PM
Best thread ever! Well done Julie and congrats to both of you.

Is your exhaust original? I know you said you have a Brituro silencer - what about the downpipes?

Super job.
Thanks Tom. Original double skinned downpipes and you are correct, Brituro silencer.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 09:58:53 PM
I tell you what seems I'm used to losing money on Italian I may as well lose on the Jap stuff too.
How about build me one good engine and you can have all what's left of the second one.
Can't be fairer then that.  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 10:02:55 PM
I tell you what seems I'm used to losing money on Italian I may as well lose on the Jap stuff too.
How about build me one good engine and you can have all what's left of the second one.
Can't be fairer then that.  ;)
I tell you what Mick, you send me the two engines and £2000 and I will send you back one perfect engine......and no change  ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 10:09:42 PM
I thought we were friends  ???
I think I will bung it in the corner and hopefully rebuild it within the next 30 years
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 10:14:04 PM
I thought we were friends  ???
I think I will bung it in the corner and hopefully rebuild it within the next 30 years
It will be worth a fortune in 30 years time. You will only be 6 years off of retirement by then as well, it will give you something to tinker with  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 10:20:57 PM
You never know 30 years time I might be on Shed & Buried  and you might spot it under a pile of crap.
It will give me plenty of time to make up a ridicules back story for it.  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 10:27:47 PM
You never know 30 years time I might be on Shed & Buried  and you might spot it under a pile of crap.
It will give me plenty of time to make up a ridicules back story for it.  ;D
In 30 years time I will be Dead and Buried and not worrying about what's in your shed  ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on January 18, 2018, 10:32:57 PM
Plan on dyeing young then do you.   :-*
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on January 18, 2018, 10:36:46 PM
Plan on dyeing young then do you.   :-*
I'm not planning to die young Mick but, who knows when your ticket is going to expire. Anyways, 30 years time I will be almost 87 and not getting any younger  ;D ;D ;D ;D :-*
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on February 10, 2018, 08:01:01 AM
Mick.   After reading Julie's rebuild thread, you should be inspired to blow the dust off your spanners and have a go yourself.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on February 10, 2018, 06:39:27 PM
I would love to strip and rebuild it myself I just don't get the same amount of spare time as you older chaps and chapets.
Its always one step forward two steps back as now I have to rebuild the little CG as my idiot brother crashed it.  ::)
I am a step closer now though as I finally got around to doing the headrace bearings on the Pegaso.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on February 10, 2018, 06:43:44 PM
If I ever get really bored and feel life's not worth living unless I rebuild another CB400/4, I will do your for you. Hope your Brother is OK?.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Green1 on February 10, 2018, 06:48:08 PM
He's fine idiots bounce well.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: royhall on March 31, 2018, 07:54:59 PM
Going back 2 days.

I put the dowels in and as these dowels have oil coming up through them, Trig said that he always fits an ‘O’ ring around the dowel, just in case. This ‘O’ ring is not mentioned anywhere in the service manual and does not come in the gasket set. Trig punched out the hole in the gasket just a little larger to accommodate the seal. I then fitted the gasket, trying it both ways round to make sure I had ‘the best fit’. In fact this pattern gasket set has been very good for sizes, shape, holes in the exact right place etc. I then dropped in the cam blades making sure they located correctly.

The extra 'O' ring Trig fitted

(Attachment Link)
Can you remember what size the extra o-ring is Julie, and what size did Trig punch out the gasket to. Nice work on the rebuild. Cheers.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on March 31, 2018, 08:04:26 PM
Going back 2 days.

I put the dowels in and as these dowels have oil coming up through them, Trig said that he always fits an ‘O’ ring around the dowel, just in case. This ‘O’ ring is not mentioned anywhere in the service manual and does not come in the gasket set. Trig punched out the hole in the gasket just a little larger to accommodate the seal. I then fitted the gasket, trying it both ways round to make sure I had ‘the best fit’. In fact this pattern gasket set has been very good for sizes, shape, holes in the exact right place etc. I then dropped in the cam blades making sure they located correctly.

The extra 'O' ring Trig fitted

(Attachment Link)
Can you remember what size the extra o-ring is Julie, and what size did Trig punch out the gasket to. Nice work on the rebuild. Cheers.
No Roy, I can't tell you the size of the O ring because Trig can't remember  ::)
But, it fitted nicely over the dowel and Trig punched the gasket out to the correct size to accommodate the O ring. I'm not even going to have a guess at the size but I'm sure you will find something that will fit and do the job.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: ogri211 on April 13, 2018, 05:47:45 AM
Would I be right in saying that the oring section would just be slightly thicker than the gasket so I would imagine that it would be a pretty thin oring and not one of these that you get in the generic oring kits also I think it would be nitrile as there is a fair bit of heat.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: BrianC500 on April 15, 2018, 10:51:39 PM
I was just reading some of the earlier pages regarding spark plugs. NGK recommend D8EA plugs in the CB400 F1/F2 not the resistor type. www.NGKpartfinder.co.uk the site is a bit long winded but easy enough to navigate.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 15, 2018, 11:28:45 PM
D8EA's are what i started using early last year to resolve a hot idle problem. Worked a treat.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 06:47:10 PM
Much excitement today in the House of Hondas, I have got all my carb bits back from the platers. I just need to find them in this pile and rebuild the carbs and I can get this old girl back on the road. Yipeeeeee, so excited.[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on April 17, 2018, 06:54:04 PM
They all look nice.

[attachimg=1]


Looks like one of these games for vintage Honda owners to while away those long dark nights out on the fens.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on April 17, 2018, 07:00:04 PM
Did you have to keep the  stuff for platers
It looks like its come out really well
I need to find a decent plater can you recommend


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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 07:08:44 PM
They all look nice.

(Attachment Link)


Looks like one of these games for vintage Honda owners to while away those long dark nights out on the fens.
Very good Nigel and yes, it's a game only people with classic bikes or cars would understand.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 07:12:08 PM
Did you have to keep the  stuff for platers
It looks like its come out really well
I need to find a decent plater can you recommend


Sent from my SM-G930F using Tapatalk
If you meant 'clean' Pete, then yes. We always use Allenchrome in Pocklington. We have never had a bad bit of metal back from them but as usual, its the cleaning you do yourself that gives the good outcome.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on April 17, 2018, 07:19:27 PM
Did you have to keep the  stuff for platers
It looks like its come out really well
I need to find a decent plater can you recommend


Sent from my SM-G930F using Tapatalk
If you meant 'clean' Pete, then yes. We always use Allenchrome in Pocklington. We have never had a bad bit of metal back from them but as usual, its the cleaning you do yourself that gives the good outcome.
When you say cleaning do you mean strip and polish or just decrease

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Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 07:37:52 PM
Did you have to keep the  stuff for platers
It looks like its come out really well
I need to find a decent plater can you recommend


Sent from my SM-G930F using Tapatalk
If you meant 'clean' Pete, then yes. We always use Allenchrome in Pocklington. We have never had a bad bit of metal back from them but as usual, its the cleaning you do yourself that gives the good outcome.
When you say cleaning do you mean strip and polish or just decrease

Sent from my SM-G930F using Tapatalk
De grease and then wire brush to clean all the s**t out of the threads and under bolt heads, in nooks and crannies etc. We actually do the de greasing in a cement mixer (easier this way with the quantity we have to do each time) with traffic film remover, fairy liquid, hot water and builders sand.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 17, 2018, 07:42:18 PM
Have you got them carbs back together and on the bike yet :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 07:46:04 PM
Have you got them carbs back together and on the bike yet :)
Nooooo Paul, I only collected the parts from the platers today.  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 17, 2018, 10:16:24 PM
Done tomorrow then ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on April 17, 2018, 10:20:21 PM
I imagine Julie is busy in the workshop,building it up,

 while Trig is making pots of tea and coffee,keeping her  supplied .

 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 17, 2018, 10:27:20 PM
I imagine Julie is busy in the workshop,building it up,

 while Trig is making pots of tea and coffee,keeping her  supplied .
You know I have to make my own tea and coffee John !!!. I'm looking at all the photos I took when stripping them, trying to make sense of how to put them back together. Give me a few days and I'm sure I will have them sorted.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 18, 2018, 08:20:44 AM
Bugger that you need them on the bike for the weekend, get Graham locked in that workshop with you ;D ;D ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 18, 2018, 08:24:49 AM
Bugger that you need them on the bike for the weekend, get Graham locked in that workshop with you ;D ;D ;)
I wish Paul but Graham is so busy with work at the moment he says I will have to do them myself. I bet my carbs will be refurbed quicker than your front forks, with all the correct parts fitted 🤣🤣🤣🤣🤣.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: hairygit on April 18, 2018, 09:13:59 AM
Stop procrastinating (Like that word!) and get on with it nursey! You took them apart, now YOU put them back together! ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 18, 2018, 09:16:47 AM
Stop procrastinating (Like that word!) and get on with it nursey! You took them apart, now YOU put them back together! ;D ;D ;D ;D
Love that word too Mr Hairy. Ok, need to go shopping this morning so hopefully make a start later today 🤞🤞🤞
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 18, 2018, 09:54:43 AM
Bugger that you need them on the bike for the weekend, get Graham locked in that workshop with you ;D ;D ;)
I wish Paul but Graham is so busy with work at the moment he says I will have to do them myself. I bet my carbs will be refurbed quicker than your front forks, with all the correct parts fitted 🤣🤣🤣🤣🤣.
Not my fault  ;D  everything states 11mm seals and I bought 11mm.
The 13mm ones will be here today so you better hurry up. Then again I do have to work as well not like some ;) ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 18, 2018, 07:49:50 PM
Stop procrastinating (Like that word!) and get on with it nursey! You took them apart, now YOU put them back together! ;D ;D ;D ;D
Love that word too Mr Hairy. Ok, need to go shopping this morning so hopefully make a start later today 🤞🤞🤞
Well, best laid plans and all that bla bla bla. Haven't had time to get anywhere near those carbs today........maybe tomorrow  ::) :'( :'(
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 26, 2018, 09:22:10 AM
The carb rebuild………A step too far for me  :'( :'( :'(

Well, the carbs are reassembled, at last. These carbs were in the most disgusting state both internally and externally and I'm amazed they were functioning at all.

These proved to a major headache for me in the end. It was all so simple in theory, strip carbs completely, every single component, taking photos and making notes, send appropriate parts for re zincing, clean all other parts thoroughly by hand and the bodies in the ultra-sonic cleaner, re assemble using said photos and notes.

Oh boy, how wrong I was. I was fine re assembling everything in the top of the bodies, the throttle arms, internal and external, the holders, slides etc. In the bottom of the bodies all the jets, float valves and needles, floats etc were easy as I had done them in the past.

The problem came when I attempted to assemble everything on the mounting plate and attach it to the corresponding parts on the bodies. Even with my photos, which by this time I admitted were useless and my notes with a few measurements of nuts and bolts, I could just not make sense of any of the parts I needed to put where. I sat there just looking at them with a total mental block, with absolutely no logic and getting in a right strop. I was even emailing Gerben, who was fantastic but I was at a total blank. So Trig did them for me. Once he had finished, I looked at them and couldn’t understand why it had been beyond me, it all made perfect sense seeing them together.

Anyway, I then carried on with the bits I can do, I have bench synced them,  re set the floats at 21mm, set the mixture screws at 2 turns out to start with and adjusted the fast idle speed adjuster.
I just need to fit them back on the bike and I’m ready to fire her up.

[attachimg=1]

[attachimg=2]

[attachimg=3]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: UK Pete on April 26, 2018, 10:00:25 AM
They look amazing

You give it your best and done 90% of the work so well done youy

Sent from my SM-G930F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: K2-K6 on April 26, 2018, 10:29:01 AM
Nice work however you got there, delegation is a very underrated skill when used at the right time!

Can't wait to see the start up results,  the suspense is killing us  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: JamesH on April 26, 2018, 10:46:24 AM
Wow, beautiful work Julie. Nice that Trigger helped do the last 1% to get you over the line  :D :D :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 26, 2018, 11:49:58 AM
Wow, beautiful work Julie. Nice that Trigger helped do the last 1% to get you over the line  :D :D :D

Trig will say he did 99% of everything James . I say Trig did 100% of the 38% I couldn't do  ;D ;D ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 26, 2018, 12:20:34 PM
Well done Julie just need to get out on it now. Dont forget the pictures ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on April 26, 2018, 10:18:08 PM
Those carbs look fantastic.   There's loads of small stuff to be zinc plated on them, it's a wonder you've got everything back from the platers, and done to a high standard.
You must tell us the name of the company that did the work.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 26, 2018, 10:27:07 PM
Those carbs look fantastic.   There's loads of small stuff to be zinc plated on them, it's a wonder you've got everything back from the platers, and done to a high standard.
You must tell us the name of the company that did the work.
Thanks Mike.
Allenchrome in Pocklington do all our re zincing. Didn't loose one single bit during plating. I'm really pleased with the way they look now, they were disgusting. I even had the start of a nest of some little critter in one of the nooks of a body. Other than the zincing, the bodies went in the U/S cleaner and the brass bits were cleaned. I already had the bowls painted and the tops polished anyway.

Edit...forgot to say don't send the big butterfly thingy, where the throttle cables attach to, to the platers, the 6 alloy rivets holding the 2 plates together disintegrate during the pickling process. I rummaged through Trigs boxes of bits and bobs and found some perfect size rivetts to repair it.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mike the bike on April 27, 2018, 08:09:55 AM
Thanks Julie.   I've got a spare set of carbs so I can refurbished them sometime.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Rozabikes Tim on April 27, 2018, 08:25:43 AM
So impressed Julie. Carbs in my mind are the hardest bit of any on these bikes to strip and bebuild.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Moorey on April 27, 2018, 08:31:58 AM
They look very nice. Do you do any prep work before sending them for re zincing.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 27, 2018, 08:33:48 AM
So impressed Julie. Carbs in my mind are the hardest bit of any on these bikes to strip and bebuild.
They are a bit of a jigsaw Tim. I suppose it's one of those jobs where it all makes sense the more often you do them......but I won't be doing any again in a hurry, I almost had to start taking Valium !!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 27, 2018, 08:35:39 AM
They look very nice. Do you do any prep work before sending them for re zincing.

De grease and then wire brush every single part to clean all the s**t out of the threads and under bolt heads, in nooks and crannies etc. We actually do the de greasing in a cement mixer (easier this way with the quantity we have to do each time) with traffic film remover, fairy liquid, hot water and builders sand.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Moorey on April 27, 2018, 04:38:30 PM
Does this just clean them or does the sand also remove the original plating. How long in the mixer roughly.?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 27, 2018, 04:50:15 PM
Does this just clean them or does the sand also remove the original plating. How long in the mixer roughly.?
No, this process cleans all the dirt/ grease etc off of the parts. Put in cement mixer fir about 20 mins.The wire brushing, preferably electric wire wheel, removes any rust and then when the platers put the parts through the pickling process, that's what removed the old zinc. You can either have them 'wired' for zincing if only a few parts or if a few Kg they put them in a tumbler all together. Tumbling is cheaper if you have a load to do.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 28, 2018, 04:00:19 PM
I have been doing the finishing bits on Hettie today. I fitted the carbs and air box etc, throttle cables and clutch cable fitted and adjusted. Engine filled with oil. Gave her a wipe over with an oily rag and  I'm all set to get her fired up.......but it's bloody pissing it down. I will just have to wait a bit longer I suppose.  :'( :'( :'([attachimg=1]

[attachimg=2]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: mickwinf on April 28, 2018, 04:11:00 PM
Thats looking really good Julie, good luck on the start up.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Laverda Dave on April 28, 2018, 05:02:58 PM
Is that the original paint on the tank Julie, looks to be in very good condition.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 28, 2018, 05:16:24 PM
Is that the original paint on the tank Julie, looks to be in very good condition.
No, it was painted about 5 years ago by the previous owner. Looks bright enough but get up very, very close and you can see it was most definitely not done by Menno Dek  ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Johnwebley on April 28, 2018, 05:33:43 PM


   that looks lovely that magic wipe with an oily rag worked wonders !!!!!!


  hope the start up goes perfectly
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 28, 2018, 05:48:55 PM
Looking great Julie you need to bag the warm workshop next time ;D ;D
Supposed to be dry tomorrow.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Nurse Julie on April 28, 2018, 06:05:37 PM
Looking great Julie you need to bag the warm workshop next time ;D ;D
Supposed to be dry tomorrow.
Do you know something Paul, Graham came out to get something from the workshop I was working in and said ' I don't know how you can work out here, it's bloody freezing', then he shot off back into his nice centrally heated engine building room!!!.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: tom400f on April 28, 2018, 07:07:51 PM
Got to say I'm a little jealous!

Post a video of the start up  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: paul G on April 28, 2018, 07:12:37 PM
Looking great Julie you need to bag the warm workshop next time ;D ;D
Supposed to be dry tomorrow.
Do you know something Paul, Graham came out to get something from the workshop I was working in and said ' I don't know how you can work out here, it's bloody freezing', then he shot off back into his nice centrally heated engine building room!!!.
It was nice and warm whilst I was in there talking with him.
You know what these southern softies are like ;) ;) you must have a bit more northern blood in you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE
Post by: Spitfire on April 29, 2018, 10:49:30 AM
That looks gorgeous, hope it runs as nice as it looks

Cheers

Dennis
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on April 29, 2018, 03:00:20 PM
🍾🍾🍾🍾🍾
Yeeeeeeehaaaaaa......Hetties up and running.

Well, in the end it all happened so fast I didn't have time to video it.

Trig kicked her over lots of times to get the oil pressure light to go out but, it wouldn't. He pushed the electric start button, engine turning over, oil light went out and then as the fuel got into the carbs she fired up. I took the front two end tappet caps off and oil was spitting out of both sides.....success.

She was idling a bit fast at 1800 rpm and a bit jittery when increasing the revs on the throttle but was running on all 4 cylinders. Smoke from the exhaust was absolutely minimal, not anywhere as much as I was expecting and that was it, I jumped on it and rode 8 miles. Stopped off at home to check the oil level, it just needed a small top up and then went off and did another 22 miles and the engine feels fantastic.

I have what sounds like a small air leak from the top of one of the downpipes which I will investigate. I now have her idling at 1200 rpm and she is hesitant at low revs when I pull away but fine at higher revs. All these things will be attended to as part of the fine tuning once I have done some more miles .I have no oil leaks and the carbs have no leaks either. 

The front forks feel great, I'm pleased I refurbed them and the front brake isn't squeaking so hopefully the disc skim has sorted that problem out.

And that's it really. I plan to get some more miles on her over the coming days and then will attend to the little issues and check everything over.

[attachimg=1]
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: andut on April 29, 2018, 03:34:24 PM
Well done on the rebuild Julie, and a great reference thread created in the process !
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: paul G on April 29, 2018, 05:57:19 PM
Great news Julie and well done great job.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Trigger on April 29, 2018, 06:06:55 PM
Great news Julie and well done great job.

Thank you Paul  ;) ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on April 29, 2018, 06:20:28 PM
Great news Julie and well done great job.

Thank you Paul  ;) ;D ;D
Haha. Paul, did you see Trig working on my bike yesterday....nope. I will not let him get away with the credit on this  ;D ;D ;D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: paul G on April 29, 2018, 07:18:02 PM
Nope he was tucked away where it was warm and dry :) :D
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: K2-K6 on April 29, 2018, 07:52:11 PM
Looks really good,  hope the initial running doesn't deliver any problems.

Holed up in a warm workshop? A proper inspection department should be at 68f and it takes quite alot of tea to maintain the correct humidity levels. ;) all in the interests of accuracy you see.

And legitimate business expense  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: GiannisFour on April 29, 2018, 07:59:49 PM
Fantastic!!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Green1 on April 29, 2018, 08:06:20 PM
Looks great  8) I bet Trigs well pleased with himself
The squeak will be back every time I think I've solved it it returns   
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Rozabikes Tim on April 29, 2018, 08:24:39 PM
That looks excellent. Well done Julie...... flash git! :P
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: waffey on April 30, 2018, 07:22:02 AM
Looks superb, it only spurs me on to get cracking on with my little 400 (same colour)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: royhall on April 30, 2018, 07:47:31 AM
Fantastic job on Hettie, Julie. It's a real credit to you, something to be proud of.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: JamesH on April 30, 2018, 08:26:13 AM
Beautiful work Julie. Congrats. She looks awesome.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Piki on April 30, 2018, 09:59:02 AM
Fantastic Work Julie, Congratulations!!!!! You will get a gift for your great Restoration!!
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: rockvegas400 on April 30, 2018, 11:17:02 PM
Looks great Julie.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on May 01, 2018, 01:44:20 PM
Sorted out the blowing exhaust headers and as a result, the hesitation when pulling away has 99% resolved itself. Just done 100 miles, no other issues presented at all. Keeping to a max of just over 60mph and 6000 rpm. This bike feels absolutely brilliant to ride and the engine is spot on.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Deano400 on May 01, 2018, 08:25:14 PM
Looks great Julie. Job well done, pat on the back I think. Long way to go on mine yet, hopefully will go as well as yours.  :) :) Very pleased for you.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: RGP750 on May 01, 2018, 08:48:48 PM
That's really nice Julie.
And my Fave colour for the 400, super job
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: haynes66 on May 01, 2018, 09:16:15 PM
that's looking great. better than i remember them in the showrooms...
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on May 02, 2018, 07:00:47 AM
Yes Ken, you are totally correct. I did remove them when I stripped them. Again, your also correct, in that photo, they are slightly off the horizontal. Those pics were taken after assembly but before I set them up. I actually noticed that flaps 2,3 and 4 would not close fully so i tweeked them on the adjusters to the horizontal which also let them close fully. Like you, I'm not sure if it makes much difference but as No.1 is fixed I thought I better get them all the same.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on May 02, 2018, 10:34:19 AM
LMAO it's my OCD Julie, I just can't help but comment when I see something like that.

Glad to hear it's been rectified, I can sleep now  :)
Luckily I don't have any symptoms of OCD Ken but, during this rebuild I have bordered on paranoia on more than one occasion !!!!
 
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Moorey on May 02, 2018, 12:04:49 PM
         
       ブラボー
        Burabō       :) :D

      shout bravo all at once   同時にブラボーと叫ぶ
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: hondarc166 on May 02, 2018, 04:49:34 PM
nice one Julie
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on May 15, 2018, 04:53:09 PM
Heading up to the 500 miles now with the running in of this rebuilt engine. Engine is feeling less tight each time I ride the bike, it is very responsive and running very, very well.  I have now started riding her quite hard, up to 80 mph @ 7000 rpm today and she would definitely give more if asked. This week I will change the oil and filter, have a final check to make sure all nuts and bolts are tight and then I will set the timing with a strobe light and set the carbs with the vacuum gauges. Both carbs and timing are very close just through me doing the static timing and bench sync of the carbs but they need  to be spot on.

I'm not going to post anything more on this thread as the damage has been repaired and the the problem resolved, so the job is complete. If I encounter any issues with the bike in the future, I will start a new thread.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: taysidedragon on May 15, 2018, 05:09:27 PM
It must be like having a new bike. Enjoy the fruits of your labour. Well deserved.  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Deano400 on May 15, 2018, 10:00:38 PM
Great thread Julie. I use it quite often for reference and probably will do through out my build. Thanks.  :)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: mattsz on November 03, 2018, 09:57:12 PM
I don't know if this is considered appropriate behavior here, but I'm bumping this thread because I just finished reading the whole thing and as a newcomer, to the forum and to the CB400F, I found it invaluable.  Forgive me if I've mis-stepped.

I've been reading through a lot of posts, I'm a bit disappointed in the number of threads where people ask questions, get some answers, but disappear without any conclusions.  I know circumstances vary, but it sure would be good to know if and how some of those questions and problems were solved...
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Johnwebley on November 03, 2018, 10:10:07 PM
Julie spent many (happy?) Hours working and compiling the thread. Afterwards explaining how the bike is running.
It is a great idea to post news of successfully cured problems. And pics if possible.

Sent from my SM-G361F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: mattsz on November 04, 2018, 12:19:11 AM
I've been reading through a lot of posts, I'm a bit disappointed in the number of threads where people ask questions, get some answers, but disappear without any conclusions.  I know circumstances vary, but it sure would be good to know if and how some of those questions and problems were solved...

To be clear: I wasn't talking about Nurse Julie's thread, I thought that one was great - some of the banter takes awhile to wade through, but it adds to the fun and I really enjoy the friendly nature of the members here!  I was thinking of a number of other threads on a variety of subjects - it's always nice, and helpful, to know the outcomes, if there are any...
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: THUNDERDOWNUNDER on June 09, 2019, 07:41:52 AM
G’day Julie , looks a good project . Could you tell me where the front brake wire  from the handle bars connects with the wiring loom ! I have put a new loom on my 400/4 but can’t find any mention in the workshop  manuals . Thanks Rob .

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Trigger on June 09, 2019, 07:53:23 AM
No brake wires from the handle bars. The brake switch is on the splitter  ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: THUNDERDOWNUNDER on June 09, 2019, 10:12:03 AM
Thanks , but I have just put a new switch/wire on my left hand side handle bar clutch lever .YELLOW AND GREEN AND BLACK WIRE . I think it is supposed to work the brake light ?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Clem2112 on June 09, 2019, 10:21:11 AM
Thats the starter lockout works like a sidestand switch
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on June 09, 2019, 10:22:16 AM
Thanks , but I have just put a new switch/wire on my left hand side handle bar clutch lever .YELLOW AND GREEN AND BLACK WIRE . I think it is supposed to work the brake light ?
No, that's the wiring for the clutch cut out circuit.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: THUNDERDOWNUNDER on June 09, 2019, 10:44:59 AM
Thanks  ,  so those wires go in the head light shell then ?
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: THUNDERDOWNUNDER on June 09, 2019, 12:55:21 PM
Thanks all for our help . Just have to find where those wires go now ha !
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on July 13, 2019, 03:26:07 PM
Just a quick update on Hettie. I have done over 2k since the engine rebuild and have had no problems at all. Having had a major overhaul with lots of machine work, I ran her in very gently for the first 500 miles, which was completely straight forward and un eventful. After the 500 mile oil change and general check over, I started putting the engine under more load and stress and gradually increasing the revs and speed, she settled down a treat. Another oil and filter change at 1500 miles. I never did bother vac syncing the carbs as she was running well enough after the carb rebuild with just a bench sync.
The only very minor issue I have had was a very slight hesitation when pulling away, so I whipped the plugs out 2 weeks ago, cleaned them and put them back in. After 30 miles hard ride, I checked the plugs again, No 1 showed evidence of running a bit rich, No's 2 and 3, less rich and No 4 spot on. I had all 4 air screws set at 2 turns out and have now adjusted them to No 1, 2 ½ out, No's 2 & 3, 2 3/8 out and No.4 left at 2 turns out. Another hard ride and plug colour is now uniform and a lovely colour.

This bike is absolutely flying. She revs extremely freely up to the red line, goes in to the red when really pushed, pulls like a train, the engine is very crisp and responsive and sounds beautiful. No more hesitation when pulling away since adjusting the air screws. Absolutely perfect all round. Also, after the front fork overhaul, she doesn't bottom out any more either and with a new back tyre fitted a couple of months ago, she handles superbly. I am enjoying every minute of riding her, she is an absolute pleasure and enormous fun.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Bryanj on July 13, 2019, 03:39:25 PM
I seem to remember that the riders handbook said not to go out of the top of the red band but mention nothing about not going into it!

Ride it and enjoy it Julie.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on July 13, 2019, 03:45:50 PM
I seem to remember that the riders handbook said not to go out of the top of the red band but mention nothing about not going into it!

Ride it and enjoy it Julie.
I have resisted going out of the other side of the red Bryan but, that is only because I couldn't stand the flack from Trig, he has a go at me for even getting anywhere near the red 🙄🙄🙄🙄
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: K2-K6 on July 16, 2019, 09:00:16 AM
After watching such an interesting thread from beginning it was good to see this bike out and about at Crich bike day.  Superb approach and detail for anyone setting out to complete an engine rebuild on a 400,  valuable reference to those following.

Good to meet both you, Julie and Graham there, with such enthusiasm for bikes in general and particularly these 4cylinder Honda.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: UK Pete on July 16, 2019, 09:41:19 AM
Just a quick update on Hettie. I have done over 2k since the engine rebuild and have had no problems at all. Having had a major overhaul with lots of machine work, I ran her in very gently for the first 500 miles, which was completely straight forward and un eventful. After the 500 mile oil change and general check over, I started putting the engine under more load and stress and gradually increasing the revs and speed, she settled down a treat. Another oil and filter change at 1500 miles. I never did bother vac syncing the carbs as she was running well enough after the carb rebuild with just a bench sync.
The only very minor issue I have had was a very slight hesitation when pulling away, so I whipped the plugs out 2 weeks ago, cleaned them and put them back in. After 30 miles hard ride, I checked the plugs again, No 1 showed evidence of running a bit rich, No's 2 and 3, less rich and No 4 spot on. I had all 4 air screws set at 2 turns out and have now adjusted them to No 1, 2 ½ out, No's 2 & 3, 2 3/8 out and No.4 left at 2 turns out. Another hard ride and plug colour is now uniform and a lovely colour.

This bike is absolutely flying. She revs extremely freely up to the red line, goes in to the red when really pushed, pulls like a train, the engine is very crisp and responsive and sounds beautiful. No more hesitation when pulling away since adjusting the air screws. Absolutely perfect all round. Also, after the front fork overhaul, she doesn't bottom out any more either and with a new back tyre fitted a couple of months ago, she handles superbly. I am enjoying every minute of riding her, she is an absolute pleasure and enormous fun.
This success story is really helping me get some enthusiasm back for doing some of mine

Sent from my SM-G930F using Tapatalk

Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: paul G on July 16, 2019, 10:10:51 AM
I seem to remember that the riders handbook said not to go out of the top of the red band but mention nothing about not going into it!

Ride it and enjoy it Julie.
I have resisted going out of the other side of the red Bryan but, that is only because I couldn't stand the flack from Trig, he has a go at me for even getting anywhere near the red 🙄🙄🙄🙄

Just don't tell him Julie  ;D ;D ;)
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Mikie on April 21, 2020, 06:07:48 PM
Hi Nurse Julie :)
I've just finished reading through this thread and I have to say you made an excellent job of the whole project.
It's an absolute credit to you. I hope you have many years of safe travels on it.
All the best,
Michael
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: Nurse Julie on April 21, 2020, 06:36:00 PM
Hi Nurse Julie :)
I've just finished reading through this thread and I have to say you made an excellent job of the whole project.
It's an absolute credit to you. I hope you have many years of safe travels on it.
All the best,
Michael
Thank you Michael. I couldn't have done it without help from him indoors, Graham (Trigger). She rides like a dream and the engine really is fantastic... The bike is no show bike by any means but she's a riders bike which is all I'm ever really interested in. I like all my bikes to look nice but its the pleasure of riding and reliability that outweighs everything else for me 😊😊😊.
Title: Re: CB400/4 ENGINE STRIP, ASSESSMENT AND REBUILD BY JULIE - NOW COMPLETE
Post by: 400 Cafe Racer on April 03, 2021, 07:30:20 PM
Hi Nurse Julie :)
I've just finished reading through this thread and I have to say you made an excellent job of the whole project.
It's an absolute credit to you. I hope you have many years of safe travels on it.
All the best,
Michael
Thank you Michael. I couldn't have done it without help from him indoors, Graham (Trigger). She rides like a dream and the engine really is fantastic... The bike is no show bike by any means but she's a riders bike which is all I'm ever really interested in. I like all my bikes to look nice but its the pleasure of riding and reliability that outweighs everything else for me 😊😊😊.

Hi Julie,
Thanks for your welcome to me as a Newbie, and please add my congratulations to yourself and Trigger and to all that has been said above by others on this major project. It has been a very engaging one to follow, with superb photos and descriptions, and I share your joy at the end.

After a short ominous engine noise on my newly purchased bike the other day, I think I may have to do a full strip/inspection to investigate if anything is in need of attention and for peace of mind, so your project is a perfect template on what to look out for on these super 400f engines.

Cheers ;D

Dennis

PS. What brand of oil did you settle on please. ?
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