Slipping clutch

[ChrisC]

For those not following my restoration blog. I am happy to say the car has just passed its first MOT however my celebrations are short lived...

The clutch slips badly under load even though it seems to be adjusted correctly. Whilst I am ecstatic that I can legally drive the car on the road - I am gutted that it has to go back into my garage for some major re-work.

So before I undo all my hard work and drop the engine and gearbox out... any ideas WHY a new clutch might slip? I know I am clutching (ha-ha) at straws...

[martins type e]

hi chris
i did read your posting and get the impression i am not allone on this planet.

though i passed already 3000 km with the fully redone car. ( 12 years by the preowner, 1 year by me) i do have a slipping clutch as well. in my case the problem was a conversion kit installed to the clutch throw out mecanism.
the mistake was no tolerance in the play of the clutch bearing to the clutch itself.
i did "repaired" this just as a provisional solution in putting spacers in between the bell housing and the engine. few 100 km later i do have a slipping clutch again. now i do guess it must have something to do with a kind of selfadjusting slave cylinder in a non self adjusting system?

i am looking forward to the following postings.

kind reagards from munich germany,
martin

[ChrisC]

An interesting temporary work around although not one I would be very comfortable with - but out of interest how big a spacer did you put in between the engine and gearbox? I assume it is simply a washer so 2mm maybe?

Can you tell us of the clutch throw conversion kit? I have never heard of anyone having one of those before and cant imagine why you need one.

[martins type e]

hi chris
i do not feel fine with this workaround as well, it just saved me 2 events i intended to take part, what was worth the improvisation.
the spacers are two washer glued together, what gave me space of 4mm between the clutch fork and the bell housing.

before that, the fork was pressed on the housing and had no free way.
i will try to ad pictures to give you more information about the conversion kit.

all this was done by the preowner, who did a unbelievable great job with the whole car, but forget to check this when mounting the engigine gearbox assembly.

till now i do not properly understand what went wrong in the second provisional situation. i do not understand what made the clutch having so much wear again. maybe it was simply the fact i did a burn out tyre test during the hot rod headbanging 1/8 mile meeting in finsterwalde?
the new slipping did not started immediately after this.

reading former postings did not bring any additional or further knowlege about the function of the different type of slave cylinders.

i did had the problem that few times the clutch did not seperated correctly and sliped only few km later.

oil on the clutch what passed by the sealings of the engine should not occure

i am looking forward for any new thoughts about your question and my posting.

cheers

martin

[christopher storey]

Chris C : do not despair yet. The most likely cause is maladjustment. The adjustment on replacement slave cylinders is notoriously fickle , and although it is more common for the clutch not to disengage properly ( see numerous posts on pushrod length ) if the pushrod is too long it may well have the effect you describe , since it will be tending to hold the release bearing in partial engagement with the pressure plate thrust pad . Since you can get drive provided not too much torque is applied, it is clear that the pressure plate is working to some extent, and that the friction surfaces have some bite in them . I should try shortening the pushrod using the threaded adjuster by about 1/8 inch at a time and seeing what it does to the clutch engagement point on the pedal - it should gradually start to engage nearer the floor with each adjustment. ( All of which reminds me - if your clutch starts to disengage the moment you move the pedal i.e. there is neither free play nor travel - then with a new clutch it is a strong pointer to its being an adjustment issue)

[ChrisC]

Darn... its confirmed. The slave cylinder pushrod is adjusted correctly and has free play..

But, the clutch fork has ZERO free play in it and the general thought is that because I have the 10" clutch - i have been incorrectly sold the longer release bearing which is used on the smaller (9.5"?) unit and with zero free play in the arm... it is partially operating the clutch unit.

So, although dissapointing - I am going to do the right thing and strip it all out again but this time fit the smaller and arguably better later clutch (seeing as my flywheel has drillings for both). Wish I had bought the smaller unit right from the start now then I wouldnt have had this problem and would be driving teh car about this sunny weekend

[1954Etype]

Ok, I'm going to join Christophers' gang.... Can you confirm that with the clevis pin removed from the end of the push rod that there is no free play on the clutch release bearing arm?

[ChrisC]

Confirmed...

Even with the push rod removed ENTIRELY- there is zero free play in the clutch release arm and I really mean zero it wont move, not even a slight jiggle. But its not like its seized in place because the clutch works with normal pedal pressure

Trust me I really dont want to take the engine and box out... i would be overjoyed if it was this simple.

[1954Etype]

Ok Chris (I thought that WAS the case but had to say it). No other option then :-(

[martins type e]

hi chris
so you have kind of the same problem like me.
putting the washers in between the bellhousing und the engine build up free way, 4 mm washers build up more than 1.5 CM (!) free way of the fork, what allowed me with a one day action to drive many days and skip the entire work till winter time, what made this whole story for me more acceptable. the clutch plate will be changed anyways so i dont care about this.
when the slippin clutch began i was willing to sell the car and my whole collection of vintage vehicles THIS time, and with the workaround it was easier to fulfill my plans of different tours.
though i am still working on other children deseases of my car.
wish you good luck.
enjoy the last summer days anyway.
cheers
martin

[1954Etype]

hi chris
so you have kind of the same problem like me.
putting the washers in between the bellhousing und the engine build up free way, 4 mm washers build up more than 1.5 CM (!) free way of the fork, what allowed me with a one day action to drive many days and skip the entire work till winter time, what made this whole story for me more acceptable. the clutch plate will be changed anyways so i dont care about this.
when the slippin clutch began i was willing to sell the car and my whole collection of vintage vehicles THIS time, and with the workaround it was easier to fulfill my plans of different tours.
though i am still working on other children deseases of my car.
wish you good luck.
enjoy the last summer days anyway.
cheers
martin

I agree with you Martin. I, too would do this and drive it. You might find another problem that can be easily solved with the engine out later.

[martins type e]

to see the pictures of my problem and my "solution" pls klick the link to the album, i did not managed qucikly to post the pics here.
herzliche gr??e aus m?nchen
martin

[/url]https://plus.google.com/photos/10295329 ... 271409[url]

[martins type e]

https://plus.google.com/photos/10295329 ... 8331271409 :D

[ChrisC]

I just cant do that... 8) it goes against my nature. If its wrong I have to fix it now that I know what the issue is. I will just write it off as another lesson learned the hard way.