Clutch slip

[Guihanos]

Hi all,

Last year, on way back to France my clutch slave cylinder leaked. I had it replaced by a local garage (who didnt know anything about TVR before). Back on the road I never tried to go flat out until February. The clutch started to slip at full throttle during an acceleration, it ends up with a burn clutch..
I removed gearbox and clutch





I put all back in with a good condition (but not new) AP clutch, and test drive, the cluch slip again... Then I removed again the GB and measure the gap between fingers and slave bearing once pull back : only 0.15mm. Is it normal? I'm thinking that with heat it may be in contact and start push the clutch..
I've previously tried the thing with removing the pedal hock and turn the back wheel while in gear and it sliped...
Does the slave bearing should be easy to pull back? Mine seemed to be filled with standard grease by the local garage... this end up by being hard to pull.
I've also heard about different length of cylinder : https://www.pistonheads.com/gassing/topic.asp?t=11...
I've also not replace the smalls washers that compensate the wearing of the disks...
here are the measurements :



Thanks for your help in advance

[THREEFISHORANGE]

Normal gap from the nose of the thrust bearing face to the fingers is about 8-10mm (on a new setup.). So when the plates wear the fingers get closer to the nose of the bearing, but still have a good clearance. Also I think pre 1998 speed sixes have the longer length slave cylinder? Hope that helps?

[Guihanos]

So according to your reply, I will do :

gap between fingers/bearing = 8~10mm when new
so
8~10mm - (thickness new clutch - thickness used clutch) - (remaining gap ie 0.15mm) = thickness of the plate I have to put at the back of the slave cylinder.
Am I right?

[Guihanos]

What is the range of the slave to get the clutch fully disengage?

[THREEFISHORANGE]

I don't think that the wear rate/dimension on the friction plate directly relates to how close the fingers move as wear progresses? Not too sure if there would be a ratio of some sort? I have done a different set up on mine, machined bell housing , replaced slave with a manufactured unit, not TVR's own .( As they can leak). Machined various parts to make mine work efficiently. I have currently done 1500 miles without issue up to press. its not a cheap option, but hopefully a fit and forget. Apologies as this does not solve your issue with your current set up.

[THREEFISHORANGE]

Guihanos said:

What is the range of the slave to get the clutch fully disengage?

I would imagine 18mm approx.?

[Guihanos]

Thanks a lot for your help ! You actually helped a lot!
I'm thinking that the grease the local garage put in the slave stuck the slave. then he couldn't be pull back properly causing slip.
I'll clean the slave and put it back in the bellhousing and check the measurement to see if there is a difference between my first check.
Hoping to find some millimeters somewhere.
It's a step forward ! Cheers

[THREEFISHORANGE]

Please be aware that the only grease to be used on the slave cylinder seals should be "red rubber grease". if you use a mineral grease it will make the seals swell or deteriorate.