Another Clutch Problem or not?

[mart155]

Hi guys,
I went out in the car today and the clutch felt a bit notchy (its the only way I can describe it) when I put my foot down on the pedal. Initially I thought it might just be the pedal that needed lubricating but it only did it with the engine running. Everything seems to be working ok and the clutch wasn't slipping at all

I'm probably just being paranoid but has anyone else had this or got any ideas or coments.
Thanks
Martin.

[Steveycaz]

Could be a number of things but the cluch cylinders could be faulty - my clutch replacement highlighted a problem with the master cylinder where the pedal felt heavy and notchy and was making it difficult to change some gears (1st and 5th)!

[mart155]

A bit more info.

Went out again today and paid particlar attention and I thought the problem had gone away. It didn't seem notchy at all when the car was cold but re-appeared as the engine got up to normal running temperature.
I can only feel it when putting the pedal down, not when releasing.
I am not having a problem getting/changing any of the gears.

I cant see why engine temp would affect it, weird!

[MikeW]

Experienced exact the same symptoms: When starting cold, pedal feel was soft and as "it should be". When getting hot, pedal feel was notchy.

I flushed the hydraulic with new DOT4, pedal feel was little better, but that was not the cause anyway.

Sometimes it disappeared completely or the pedal felt like there was something jamming inside the clutch.

As I had no clue, I considered it as a proplem with the grease on the shaft for the throw-out bearing.

Misfortunately my clutch went broken some days later (I assume the the damper spring thing on the discs due to analogical noise and intermittend engaging problems). But this is very sure a different thing.

I'll put out my clutch next week, maybe then I will find the reason for it.

[TheSebringOne]

When DTM brought his old yellow NSX, he had problems with the clutch & gear change with not enough lubrication on the shaft! :eek: :laugh: On a serious note DTM can you confirm?

It could also be the release bearing or the pressure plate, where there maybe a bent or two falcrum springs?

HTH :)

[markc]

Martin,

The problem you describe sounds a bit like the one I had with my clutch. It was inconsistant, sometimes normal and sometimes stiff and "boingy". The take up point also varied as it got got warm/hot. This turned out to be a distorted pressure plate which you could see by 3 shiney high spots on the surface. The friction plate had plenty of material left, the release bearing felt OK and the flywheel surface was fine as well. Of course I changed the pressure plate, friction plate and release bearing anyway but left the original flywheel. It's been fine since ie for the last year and a bit.

My car was/is very low mileage and I suspect as the clutch had just sat there unused for long periods it had warped slightly.

The only problem with this theory is that mine is a 3.2ltr car which has a completely differant clutch to yours.

Mark

[mart155]

Thanks for your comments guys, I hope it isn't the clutch itself for obvious reasons.
This clutch has only done 14k miles but it was changed quite a while ago by the previous owner. August 2004 to be precise.

When you talk about lack of lubrication, are you referring to the gearbox shaft that the release bearing slides on to press the fingers of the pressure plate. Is there any way to lubricate this

[WhyOne?]

I cant access Prime from work, but if you do a search on 'clutch judder' you will find a number of references to the symtoms/problem described by markc. The distortion of the pressure plate seems to be quite a common problem and of no real consequence to the longevity/performance of the clutch as long as you can live with the juddering.

[markc]

Hi Martin,

The release bearing itself doesn't actually touch or slide on the input shaft, the friction plate is the only part of the clutch assembly that does this. The release bearing presses onto the cover plate fingers as you describe (no lube needed at that interface) to unclamp the pressure plate from the friction plate and thereby "de-clutch" the engine from the gearbox. It, the release bearing, pivots on an arm (operated by the clutch slave cylinder), it is this that may need a little lube at the pivot point and aslo where it connects to the slave cylinder. The only part you can get at to lube with everything still in situ is that last part and it is IMO highly unlikely to have any effect.

Mark