Clutch

Post by **bmcecosse** » Tue Apr 28, 2009 10:45 pm

If the pedal has been low because of missing spring - the carbon thrust will have been rubbing constantly against the clutch release pad, and will have worn away. It's 'engine out' to fit a new one. But no harm in adding washers etc to the linkage - as long as you keep ~ 1" 'free play' at the pedal it won't come to any harm.

Post by **katiekat** » Wed Apr 29, 2009 7:50 am

Thanks for all the advice! I'll have another look at it today - hopefully it will be alright.

Post by **kennatt** » Wed Apr 29, 2009 8:22 am

Katie the adjustment is only to take up wear in the external linkages,and to set the free play so that the clutch is NOT being held by the pedal when your foot is OFF.If it was the carbon thrust and clutch would wear rapidly.There is no adjustment possible with ithe internal parts of the clutch so the biting point will always be where it is.If you renewed the whole of the internals then the biting piont may be higher,lower or the same as it is,there is no way of adjusting it.It depends on the thickness of the new parts,if they are slightly thicker than the old then the point will move.As long as you are getting all gears without crunching(Except 1st which has no syncromesh) and the clutch is not slipping or making excessive noises then all will be fine.The only other thing could be that the actuating arm that goes from outside to the inside of the clutch is bent that would alter the biting point,but you would then be having problems with the clutch not disengaging and gears crunching so not very likely.

Post by **katiekat** » Wed Apr 29, 2009 9:40 am

Thanks Kennatt. I wanted to get it sorted as I have a problem with my feet called plantar fasciitis and the doctor says I've also got arthritis now. I don't want to have to press the peddle hard as it hurts!

Post by **mike.perry** » Wed Apr 29, 2009 12:06 pm

The workshop manual says there should be 3/4 in free play at the clutch pedal. This ensures that when your foot is off the pedal the return spring keeps the thrust bearing which has a carbon face away from the clutch pressure plate and prevents the carbon from being rubbed away.
If you adjust the clutch rod so that you have the correct free play then the biting point will be slightly higher and it will ensure that when you depress the clutch pedal then the clutch will be fully disengaged which will reduce gear crunching

Post by **bmcecosse** » Wed Apr 29, 2009 1:26 pm

There are different 'free play' sizes quoted for different engines - and different manuals! Hence I suggested 1" as a sort of average! It's really not that important - as long as there IS some free play!

Post by **kennatt** » Wed Apr 29, 2009 6:30 pm

the biting point will not move whatever you do to the free play it cant it's the point where the clutch friction plate starts to come into contact with the pressure plate,the free play only adjusts free play.It will move the point where you start to feel the pressure plate move on the downwards stroke but thats all. Once the cluch pedal is fully depressed the free play has gone and as soon as you lift off the biting point will be in exactely the same place regardless of where the free play is.There is no way to alter the friction plate or pressure plate in relation to each other,They are fixed by the distance between the flywheel and pressure plate which are bolted to each other and therfore can not move in relation to each other

Post by **bmcecosse** » Wed Apr 29, 2009 7:53 pm

Yes - I don't disagree with that, but you won't have to push the pedal through all the 'free play' to get there, so effectively the whole action range will move upwards.

Post by **mike.perry** » Wed Apr 29, 2009 9:19 pm

The biting point may not physically move but will move in relation to the amount of free play in the clutch pedal. Too much play and the pedal will be too near the floor and won't disengage the clutch fully, too little free play and the thrust bearing will be in permanent contact with the clutch plate and will wear out

Post by **kennatt** » Thu Apr 30, 2009 7:24 am

[quote="mike.perry"]The biting point may not physically move. QED.

Post by **katiekat** » Thu Apr 30, 2009 8:25 am

Thanks for all the advice. I didn't realise that you couldn't move the biting point.

Post by **mike.perry** » Thu Apr 30, 2009 9:15 am

I've forgotten what the original question was, just reading back to check.
Forget about all the technicalities, adjust the clutch rod to leave a little free play at the pedal and it should be OK.

Post by **katiekat** » Thu Apr 30, 2009 11:33 am

Do you think the clutch might need a overhaul?

Post by **mike.perry** » Thu Apr 30, 2009 11:57 am

Adjust it up as instructed and try it out. If you still have problems with it then we can go from there.

Post by **kennatt** » Thu Apr 30, 2009 2:48 pm

as last ,try it, sounds as though it will be fine.

Post by **katiekat** » Thu Apr 30, 2009 3:45 pm

I've adjusted it as much as it will go but the clutch is very difficult to use as it's so firm and the biting point is so low. It sort of takes the enjoyment out of driving her so I'll definitely have to get it looked at.

I wouldn't have a clue myself where to start!

Post by **alex_holden** » Thu Apr 30, 2009 3:58 pm

I bet the problem is worn linkage/disintegrated relay shaft bush.

Post by **katiekat** » Thu Apr 30, 2009 4:29 pm

Sounds expensive!

Post by **alex_holden** » Thu Apr 30, 2009 4:36 pm

http://morrisminorspares.co.uk/shop/pro ... ts_id=2343

Post by **katiekat** » Thu Apr 30, 2009 5:09 pm

That's not bad £24.50. Is it hard to fit?