new clutch problem

[macdeb]

Installed a new AP 500ft/lb clutch. Now the problem is that it will not disengage properly, especially when warm. Looks like the actuator arm with release bearing is not travelling far enough against pressure plate [cover]. So, what now? Bigger bore master cylinder maybe? Anyone else had this problem? Or any other ideas? I have changed the fluid and bled it again and again with no improvement. cheers.

[haircutmike]

If it worked fine before,
(clutch slave), it should work now.

Have you definitely the correct clutch fitted?

I didn't realise, I had the wrong clutch fitted to my car and it started slipping prematurely!

Worth a check.

[Simon says]

Hi Mac,my brother as just fitted an Helix/AP/v8Dev 500 spec clutch and had exactly the same problem as yourself I had driven he's car in the past and noticed the clutch pedal travel was slightly less than mine but was causing no issues so was left alone,last year when the original clutch started slipping (due to wear & tear) he fitted the super duper clutch down at my shop and noticed that the clutch pedal needed to go all the way to the floor to engage gear at this point we was running out of time so he decided to drive home anyway presuming it may just need a bleed unfortunately this did not improve things so he decided to investigate further the short pedal travel instead this turned out to be his problem the pushrod to master cylinder piston was incorrectly adjusted (to short) so he wound this out till both brake and clutch pedal were level to start with (longer stroke) this cured the problem and he is happy once more worth a check methinks.

[macdeb]

Mike, yeh, new one was specced by John Eales and recommended by DBV8.
Simon, yeh, seems the travel is insufficient and the biting point is right at the bottom of travel it was Johns suggestion about upgrading the master cylinder as with a bigger bore will push a greater volume of fluid for the same pedal travel as i understand it and am sure I've heard of a similar solution to this on here before. However, your suggestion about the adjustment makes good sense and I will have a look as soon as I can but am away now for a week and half which only leaves me with a couple of days to sort before Santa Pod on 9th Cheers guys for replies
Anymore??

Edited by macdeb on Sunday 26th June 20:47

Edited by macdeb on Sunday 26th June 20:49

[rev-erend]

Mac - when I fitted a larger single plate McLeod clutch ..

I measured the height of the plate, clutch and bearing and did the same with
the standard clutch.

The new clutch was 10mm highter .. so I just have the bearing carrier
lathed down by 10mm.

[Ribol]

macdeb said:

.............upgrading the master cylinder as with a bigger bore will push a greater volume of fluid for the same pedal travel as I understand it and am sure I've heard of a similar solution to this on here before.

Keep in mind that it will also significantly increase the effort required at the pedal end, adjustment would be the best way out if you can get away with it.

[Simon says]

Ribol said:

macdeb said:

.............upgrading the master cylinder as with a bigger bore will push a greater volume of fluid for the same pedal travel as I understand it and am sure I've heard of a similar solution to this on here before.

Keep in mind that it will also significantly increase the effort required at the pedal end, adjustment would be the best way out if you can get away with it.

Not quite sure you should have to resort to this really after all it should just work as Ribol says adjustment should be enough

[macdeb]

rev-erend said:

Mac - when I fitted a larger single plate McLeod clutch ..

I measured the height of the plate, clutch and bearing and did the same with
the standard clutch.

The new clutch was 10mm highter .. so I just have the bearing carrier
lathed down by 10mm.

Alan, I compared old with new and they looked to be the same dimensions though didn't actually measure the combined height. Could it be that my new is lower explaining extra travel needed? [sure I'm missing something] hows yours performing?
PS; Still loving that 'KH'

Edited by macdeb on Monday 27th June 20:28

[macdeb]

Ribol/Simon says, At the moment don't mind the effort as long as it works [sure my opinion will change when in traffic]. I did go back into the garage last night at 10.30pm after reading Simons advice, tried it for travel this morning and whilst it is better the biting point is still only just off the bottom. I'm off on hols for a week tomorrow so doesn't leave much time to solve on my return, please keep advice coming as it's very much appreciated and thanks to all so far. If I don't reply straight away I will on my return, cheers

[Simon says]

macdeb said:

Ribol/Simon says, At the moment don't mind the effort as long as it works [sure my opinion will change when in traffic]. I did go back into the garage last night at 10.30pm after reading Simons advice, tried it for travel this morning and whilst it is better the biting point is still only just off the bottom. I'm off on hols for a week tomorrow so doesn't leave much time to solve on my return, please keep advice coming as it's very much appreciated and thanks to all so far. If I don't reply straight away I will on my return, cheers

No problem Mac,well done putting our names in order of age too oh! hello Ivan

[rev-erend]

macdeb said:

Alan, I compared old with new and they looked to be the same dimensions though didn't actually measure the combined height. Could it be that my new is lower explaining extra travel needed? [sure I'm missing something] hows yours performing?
PS; Still loving that 'KH'

Edited by macdeb on Monday 27th June 20:28

She is lovely

I actually attached both clutches in turn to the flywheel with it on a flat surface then measured to the flat spring plate .. 10mm was a lot of difference.

[macdeb]

rev-erend said:

She is lovely

I actually attached both clutches in turn to the flywheel with it on a flat surface then measured to the flat spring plate .. 10mm was a lot of difference.

Flywheel was still attached to car and to be honest it never occured to me to measure the height. When bolted to flywheel the fingers were 'flat' as opposed to cone shaped proir to fitting.

[macdeb]

Quinny said:

Mac...

Has the arm, been fitted onto the thrust bearing the right way around...??

The bearing has a round side and a flat side, but the slipper pads will fit either side..... If the round side of the bearing is facing the in towards the arm, it will restrict the movement..

Cheers bloke, yup, thrust/release bearing fitted right way. I'm sure I've read on here before about changing master cylinder also with some clutch upgrades, but the search engine isn't the best.