400/4 low oil pressure + Other Misc problems

[Binman180]

Good afternoon  gents,

I've spent some time cleaning the clutch up on my 400f (it was full of shit and rust) and replaced the plates. However upon reassembly I have two problems:

Problem 1: the kick start lever doesn't seem to return after being depressed, I've checked around the area and cant see anything suspicious. So any ideas on that?

Problem 2: after reassembly the oil pressure light doesn't seem to be going out. It took a while for it to go out when I changed the filter before I dod the clutch but I cant really remembe how long this took, it doesnt seem to go out now though. So how long does the engine normally take to gain oil pressure after oil/flter changes and where am I going to start looking for problems? Could the oil pump be bollocks, could there be shit in an oil way? If so where would this most likely be?

I'm going back tomorrow to look at it again so if you guys could give me some ammo to work with, that would be great!

[Binman180]

Just looked at this 350f/400f shop manual I got off the web, I'm gonna drop the sump tomorrow (should have done it anyway) to see if the oil filter screen is covered in crap and inspect the oil pump too.

[ka-ja]

Hi,
    Possible cause of kickstart not returning,is the return spring "hook" not being engaged in the right position in the crankcase casting, engage the kickstart return spring along with the shaft before fitting the clutch cover.
   I have known of the the oil pump suction filter to be partially blocked, usually caused by excessive use of jointing compound of the setting variety, ie. silicon and one time with blue hyomar, and yes, it does take a while to ( almost a minute on a overhauled oil empty engine) fill the oil galleries and filter. I personally refill an empty engine through the tappet covers, 1/2 each end of the cyl. head, to help the oil feed lag on starting.Over time, oil pumps gradually fade, unless of course, a foreign body gets in it and strips the teeth.
       Hope this helps-----Ken

[Binman180]

Hi Ka-Ja,

Thanks for your reply, I discovered that everything was fitted properly with the kickstart lever, however out of desperation I had to replace the old cover gasket with a card one which was thinner and when the cover was tightened it bound the kickstart up a bit, slackening this off has sorted the problem out and it should be fine when my new gasket comes through the post.

The oil pressure ended up being fine once I popped the oil pan off and cleaned the crap out and the oil screen.

I have now discovered another problem!

Problem 1: I am getting clutch slip, this occurs when i'm at about 30mph and open up past 5 - 6k, The cable has slack on it and I believe I assembled the clutch correctly (Steel plates with he sharp side of the lugs pointing toward the engine), I also replaced the springs when I replaced the friction plates. I am using Halfords Classic motor oil 20W-50W (Link: http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_166289_langId_-1_categoryId_165581)

Problem 2: I cannot seem to reliably shift down, Especially from second to first. shifting up seems to be ok-ish but shifting down at times seems to leave me pressing on the lever without anything engaging, whether rolling forward/backward with the on or off.

Possible Problem 3: The engine seems to be quite rattly, I'm not experienced enough to tell whether or not this is a bad thing and I've herd these engines are generally quite rattly. Sounds like a chain to me, the sound is coming from the centre of the cylinder head however. the cam chain pensioner bolt looks to me like it is out of travel. I'll upload a couple of pictures and a video on my phone later.  EDIT: Attached should be a picture of the tensioner bolt (Might have a couple mroe turns left in her but she doesn't look good as far as a seized bolt is concerned, haven't tried it)

[ka-ja]

Hi Binman,
                !st of all, I would question the oil you have put in, spec. says 10-40grade, and according to others, steer clear of fully synthetic, although it hasn't caused me problems, but 20-50 could certainly cause clutch slip, and it could also cause clutch drag,enough to hamper gear changes.
                Also hope you was aware that one of the friction plates is different to the others, and sits on the outside of the other plates, setting up the clutch with the end adjuster should be done before the clutch cable is fitted.
             The camchain adjuster bolt is a locking device for the internal spring loaded adjuster.
                As for the cam chain adjustment, an old dodge is (with engine running) to remove the cap screw from above the the adjuster bolt between the front mounts, and when you slack off the adjuster lock screw,push down hard through the uncovered top hole with a bit of bar, then tighten the adjuster screw back up. This will not however correct for a worn camchain or seized adjuster.
              And to add to all that, the primary drive chain can wear and rattle, built in internal rubber shocks (in the starter clutch and clutch) can solidify with age causing rattles, and of course carbs out of sync are also rattle causing.
              I would get some 10-40 in it for starters.-----Ken
               

[Binman180]

I will try a different oil then, I did notice that one of the clutch plates was thinner to account for the snap ring on the outer steel plate of the clutch assembly.

Will the Halfords Semi Synth 10w40 be ok to use?
 (Link: http://www.halfords.com/webapp/wcs/stores/servlet/product_storeId_10001_catalogId_10151_productId_221725_langId_-1_categoryId_165507)

 I herd a murmur that modern oils can be dodgy in old engines.

And Could Engine oil alone really be causing that much trouble with gear changing? I had a friend pushing me with the engine off at one point trying to get out of second. is there anything else to look for or other suspected points? Any linkage? (I think there's some under the clutch cover). Attached is a picture from under the cover, unfortunately I lacked the foresight to take a decent photo of it square to the bike


As for the cam chain adjuster bolts, I'm a bit sceptical to try it at the moment as from the pictures I attached the bolt looks quite rusty and I'm worried it will break off. any get out of jail free advice with that? Maybe wire brush the bolt from the outside to help with the nut and heat the engine up with some penetrating spray and light tapping with a pin hammer before I work it with a socket?

[tom400f]

See oil discussion here: http://www.sohc.co.uk/index.php?topic=6662.msg36747

For the camchain bolt - yes it is easily broken off. Penetrating spray and leave for a few days, heat with a small blow torch, loosen the locking nut and use a small spanner only. Tap to loosen corrosion - all those things. Be very careful.

[ka-ja]

Hi,
 Concur with the others, wrap some rag around the adjuster lock nut to hold the penetrating oil longer.
  If you remove the selector arms etc for examination, you should be able to check gear selection by turning the selector drum by hand, may need the output shaft(sprocket) moved back and forth to mesh the gear teeth.
       One obvious question, did these problems all occur before or after the clutch clean?----Ken

[Binman180]

Oddjob,

I've dropped the oil pan and there was quite a bit of sludge and a little gritty stuff in there (Not much) so the sump hasn't been cleaned out for a while. but whilst I had it off I did take a quick glance up through the engine and I couldn't see any damage on the gears.

I think I'll try the oil first, take the clutch plates out, inspect what I can and give the plates gunwash bath, and refit/oil with the proper grade oil and go from there.

I shall try the penetrating oil rag trick next time I go up to look at it.

Thanks for your advice gentlemen!

[K2-K6]

You can also make a small pocket of something like blue-tak if you want to soak it in penetrating oil...something like a kangaroo pouch type thing to leave it a while.

[Binman180]

Sorry for reviving an old thread,

FINALLY after a few months, I've got the bike home properly and took the exhaust off and front brake caliper.

Unfortunately during my first inspection I missed a bloody hole in the bottom of the silencer (Attached) and a single bent spoke on the front wheel (Does anyone here think that a single bent spoke on the front wheel is anything to worry about for the time being?).

The exhaust sounds like a maraca and after poking my finger through the hole a load of rust pours out... So I'm going to look at making a stainless exhaust in the near-ish future, probably not TOO difficult.

I took the caliper apart to find a fair bit or corrosion on the inside and the piston has some pretty bad pitting, after machining a new piston out of stainless bar stock to the dimensions of the old one, fitted it back together and bled the system however it doesn't feel like there is a great deal of power there, the lever can, with a bit of grip, touch the bars and the pads don't seem to reset properly (Slight bind). Am I over estimating the brakes power? or is this just how they are?

P.S: I changed the oil from the 20w50 stuff for halfords 15w40 and that has cleared up the clutch slip dramatically and also I believe it has solved the sticky gear change since I haven't encountered a problem yet. thanks for everyones advice on that.

Thanks, Ryan

[Johnwebley]

my experience with the brake is the caliper seal hardens,causing some of the problems,it is the flex in the seal that retracts the piston,
they  are cheap as chips to replace,so try that ,and see how the brake is after,

[Binman180]

Thanks for your reply John, But I forgot to mention I have already replaced the seal  , I'm gonna take it apart again tonight and try to clean it up a bit better.. maybe I missed a bit of corrosion somewhere