Thread: Really caught - trying to get the clutch to engage

Originally Posted by 1950landy

Is the clutch plate exactly the same diameter as the old one , why I am asking is I bought a new clutch plate once & it was slightly bigger than the original , like 1 to 2mm's & the outer edge was touching on the pressure plate housing . had the gearbox out about ten times until I worked out the problem . Probably not that but worth checking.
You could also check that you do not have too much end float in the crank shaft causing the flywheel to move forward causing you to run out of travel on the throw out.

Just checked the clutch plate - identical to the old one. The one I’d removed was 3.5mm thick and almost on its rivets and the new one 6.8mm. That was the only difference.

I’m starting to suspect the linkage to the slave cylinder and will check that out when I get it all together.
Thanks again.

Finally got the clutch to disengage this morning. The gearbox was only out 3 times so I guess it could have been worse.
I bought new linkage which removed all the play, made sure the slave was properly bled and then changed the splined cross shaft (I couldn’t get clutch on the 11mm in the manual) until it worked.
Now when the release bearing is not engaged there is about a 5mm gap before the fingers. I guess that’s OK?

Originally Posted by Ricrose

Finally got the clutch to disengage this morning. The gearbox was only out 3 times so I guess it could have been worse.
I bought new linkage which removed all the play, made sure the slave was properly bled and then changed the splined cross shaft (I couldn’t get clutch on the 11mm in the manual) until it worked.
Now when the release bearing is not engaged there is about a 5mm gap before the fingers. I guess that’s OK?

untill the clutch is about 1/2 worn it'll be fine.

I figure that would be the case - I think I’ll have to adjust again - it really is a compromise!
I don’t fancy removing the gearbox once the resto is finished.

you dont need to remove the gearbox to adjust it.

theres a length adjustment on the push rod.

set it up so the push rod is fully extended with the forks at the 5mm distance and the bearing is face is extended from the rest position by say 20mm. then as the clutch wears you shorten the rod letting the push forks rotate backwards to accomodate the play.

the II/IIa clutch is a little bit of an artform but its key to remember that its still a hydraulic system that is largely self adjusting. once you've set it up mechanically with the throwout bearing clearance checked with the slave in the 1/2travel position you need to have enough mechanical adjustment/piston retraction to get the 11mm clearance from a new clutch.

once you have the mechanicals up and in postition 99% of your throwout bearing freeplay is going to vanish as they hydraulics do their bit.

I personally always aim to hit

rod at 3/4 max lenght
piston at 1/2 face travel
throwout bearing .5mm off of new clutch fingers.

Remember if your putting a SIII pressure plate onto a SII clutch throwout you need an adaptor that sits between the fingers and the throwout as the III's fingers sit in a different position to the levers on a II clutch

You wont get a good adjustment without the adaptor

if you find the piston is bottoming out on retraction then you can space the MC body up about 1/4 of an inch without too much hassle by adding a spacer plate or washers and slightly longer bolts.

Question for Dave - the Series 2a pressure plate is harder to find than the S3 one, because, as you say, it has the spacer attached to it. It occurs to me that it would be relatively easy to turn a spacer that attached instead to the thrust sleeve, probably by having a recess to fit it closely, and held in place ideally by a circlip, although I'm not sure there is room with the sleeve fully retracted, or a pair of grub scres. Balance would be a bit critical, and the face might need to be hardened - or would it?

Thoughts?

Originally Posted by JDNSW

Question for Dave - the Series 2a pressure plate is harder to find than the S3 one, because, as you say, it has the spacer attached to it. It occurs to me that it would be relatively easy to turn a spacer that attached instead to the thrust sleeve, probably by having a recess to fit it closely, and held in place ideally by a circlip, although I'm not sure there is room with the sleeve fully retracted, or a pair of grub scres. Balance would be a bit critical, and the face might need to be hardened - or would it?

Thoughts?

nope,

4074.jpg
A proper series 2 plate, bit heavy on the leg
5427.jpg5
a modded SIII style plate for the SII/SIIA
6827.jpg
Seires III plate.

not hard to find at all, My usual goto's can get them and they're available from UK suppliers.

I didn't say they were hard to find, just harder, and if I needed to do one, I would probably get the proper one - I was just wondering whether my suggestion would work.

And on that subject, for my ex army 1970 2a, I am guessing it has the later 9.25" clutch with the pressure plate similar to the S3. Can I assume this (I know it hasn't been changed since it left the army), or do I have to look?