Today i replaced the Spring diaphram type clutch on grey.
Machined flywheel and backing plate, new drive plate, bearing, gear oil seal. Everything cleaned carefully, installed and adjusted to manuals specs.
Clutch is still slipping , making new noises and not engaging properly after many small various adjusting .
WHAT THE HELL!!
Any suggestions please.
Thanks Anthony.

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Dog Food! Most kids like it more than Broccoli.

a common mistake made when machining the backing plate is to machine the clutch face, but neglect to machine the same amount of metal off the posts that go through the flywheel, essentially making the backing plate run further away from the flywheel, and reducing the clamping pressure the diaphragm can put on the clutch plate.

onions for onions I'm sure that's what has happened

the way to check it is to assemble the clutch/flywheel/backing plate/diaphragm on the bench and look at how well compressed the diaphragm spring is - it should be almost parallel with the flywheel. I did a clutch on a clubman once, and it needed .060" taken off the posts to get any clamping pressure on the clutch. You'd be able to take tke clutch cover off the car and look at the spring the same way, if it's at a significant angle to the flywheel, there's your problem

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All stems were machined.

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Dog Food! Most kids like it more than Broccoli.

What a PITA

Tell us what adjustment routine you went through

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1967 Cooper S - new front bearings to do.
1965 Cooper S shell - Slow progress. No time or money!
1966 Deluxe- next rustoration!
Mk 2 & XJ6 Jags. Less said the better.

Did you happen to measure them?

From memory they should be 490 thou higher than the pressure plate face. If they are significantly larger than this the clutch plate wont be "sandwiched" sufficently causing the clutch to slip.

Try backing off the adjustment just until you can put it into reverse with any grinding etc. and see if that makes any difference.

For the clutch to slip there has to be something fundamently wrong with it, especially if the clutch is adjusted properly.

Sorry to hear about your problems - the clutch isnt a very fun job and especially to redo it so soon afterwards. A real PITA as you said.

Do you have a lightened flywheel or anything? If you do make sure you have the compatible backing plate and make sure it isnt binding up on the flywheel. If it is the same stuff as you had in there before and it was working fine (before it failed) you can rule this out.

I have to do a clutch in my grey '64 mini this week too. Must be the time to do it

Best of luck.

Matt

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After double checking and pestering people about proper adjustment i now have no slip while driving.
However release spring is off.
When i put it on i have to pump the pedal to be able to select gear.
Is it ok to leave the spring off
Also with clutch pedal depressed and in gear for a period of time, clutch starts to disengage. Is this a symptom of worn slave and or master cylinder

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Dog Food! Most kids like it more than Broccoli.

definitely a slave or master cylinder problem! (more than just onions this time)

clamp the slave cylinder hose with some vice grips and try the pedal - if it's a bit soft and slowly sinks to the floor, your MC needs a kit, if it's rock hard and stays that way, your SC needs binning & replacing.

Just to double check before you start working on either one, when you take the metal pipe off the top of the MC, put a bleed nipple in there and try the pedal again - should behave the same as when you'd clamped the hose

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did I tell you that I won a trophy?

Thanks Bro! I LOVE ONIONS

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Dog Food! Most kids like it more than Broccoli.

By "release spring" do you mean the spring that sits on top of the slave cylinder??

If so, then you systems are entirely consistent with a clutch that hasn't been adjusted.

With the spring off, how big is the gap between the clutch lever and the bolt that goes into the clutch cover about half way down the lever?

Any more than 10 to 20 thou and you're in trouble.

Normally, if the gap is right, the presence or otherwise of the spring will have no impact. The fact that your clutch sinks over time when engaged suggests a defective master cylinder. But I don't really think that your release spring is strong enough to cause the effect you describe.

Cheers, Ian