Honda-SOHC

SOHC.co.uk Forums => CB750 => Topic started by: p@ul on January 03, 2013, 09:56:43 PM

Title: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 03, 2013, 09:56:43 PM

I'm ready to remove the engine form the frame of my F2 but need to remove the stubs from the cylinder head. i have a Haynes work shop manual that covers all sohc 750's that states " the stubs are retained by 2 cross head screws " with no mention of a mod to the F2. I cannot see any screws retaining the stubs and i'm at a loss how i can remove them without causing damage to the stubs or cylinder head. They look quite corroded so maybe stubborn to shift at best !!
What's my best course of action  ?

Thanks Paul.

Title: Re: Cylinder head exhaust stubs removal ?
Post by: UK Pete on January 03, 2013, 10:41:44 PM

Hi F2's should have studs with nuts, do you have any pictures
Pete

Title: Re: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 03, 2013, 10:47:37 PM

Hi Pete, my F2 is the US version of yours if that helps.

Cheers Paul.

Title: Re: Cylinder head exhaust stubs removal ?
Post by: Bryanj on January 04, 2013, 08:10:45 AM

ALL F2's should have two studs per cylinder, only the early K's had stubs and you did not have to remove those to get the engine out!

Title: Re: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 04, 2013, 01:39:17 PM

Ah right so you're telling me i don't need to remove the studs to remove the engine on my F2 then, that's good but its going to be mighty tight to pull the engine out then. I tried doing it on my own last night but just ended up giving up...... I'll get my son  to give me a hand i think.

Cheers Paul.

Title: Re: Cylinder head exhaust stubs removal ?
Post by: tom400f on January 04, 2013, 01:56:11 PM

You could always try the technique of lying the frame down on its side with the engine in it and lifting the frame away from the engine once the bolts are removed. I've not done it but I believe its a method others on here have used.

Not sure how easy it is to manhandle a 750 engine (unless you are Geoff Capes that is  :P)

Title: Re: Cylinder head exhaust stubs removal ?
Post by: Bitsa (Ralph Wright - RIP) on January 04, 2013, 02:03:52 PM

HI Paul.
Like they say, it does come out but unless like someone mentioned your like Capes its fairly easy with two.On sunday I am going to put mine back with my mates help.He is well knowledged on this as he has helped for the fourth time.Be done in five Min's.
Take your time best of luck
Bitsa

Title: Re: Cylinder head exhaust stubs removal ?
Post by: Bryanj on January 04, 2013, 02:36:14 PM

As long as you have the oil filter off it is possible but easier with the sump and rectangular top cover off as well.

It can be done on your own but wear a back brace or startpracticing soprano singing

Title: Re: Cylinder head exhaust stubs removal ?
Post by: K2-K6 on January 04, 2013, 03:55:46 PM

I've always done as Bryanj says with sump and top breather cover removed......but will add that I take the oil pump off to avoid clobbering it on anything.

If you look at the clutch side of the engine.....then rotate it anti-clockwise just far enough so that the lugs on the engine clear the coresponding frame lugs then it comes out slowly but quite easily.....I've always had two people also to ensure you can do it well.

Maybe worth taking off any of the breather pipe guides on the back of the gearbox as well if it has them.

Title: Re: Cylinder head exhaust stubs removal ?
Post by: UK Pete on January 04, 2013, 05:49:18 PM

Hi paul i understand what your saying now, yes it does help to take out the exhaust studs, if you put two nuts on the stud and lock them together then put the spanner on the bottom nut and undo the stud should come out, yes the engines on these have very little room for fitting or removal, as mentioned in above posts remove sump cover and top breather cover, plus studs and you will have an easier job removing it, but the best way is laying the frame on its side and taking out the engine bolts then just lift off the frame from engine, simples i say, but only if your prepared to strip everything off the bike so its frame and engine left
Pete

Title: Re: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 04, 2013, 07:09:27 PM

Hi Pete, now I understand...... I have stated in previous threads that I am a little inept at this sort of thing  :)
The motor is now sitting loose in the frame but I guess I could re install the 2 front left side mounting bolts and maybe 1 bar before I have a go at those pesky studs..... Thanks a lot for the sound advise. I will tackle the engine removal this week end, and yes I am right down to bare bones main frame and engine now so nearly there  ;)

Title: Re: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 04, 2013, 07:15:33 PM

Thanks to everyone for the input.... I feel a little more confident now ;D

Title: Re: Cylinder head exhaust stubs removal ?
Post by: UK Pete on January 04, 2013, 07:25:19 PM

Good luck Paul, you will not believe how easy it is with frame on side

(http://i924.photobucket.com/albums/ad90/UK-Pete/cb750/PICT6631.jpg)

(http://i924.photobucket.com/albums/ad90/UK-Pete/cb750/PICT6628.jpg)

Title: Re: Cylinder head exhaust stubs removal ?
Post by: p@ul on January 06, 2013, 10:18:17 PM

Well..... I got the engine out today thanks to all the tips and advise. Got the studs out and breather cover off. However the sump cover wouldn't budge, I tried a little gentle persuasion with a screw driver but it wasn't moving...... Any tips ?
Also the removal of the top rear engine mount bar revealed a broken lug on the engine casing..... Not a major issue but could this be fixed I wonder ?

Cheers Paul