What causes clutch judder?

[Fruitcake]

I had it in my old Punto now I get a bit of it every now and then in my current car and just want to know what causes it, basically.

Also, is it serious?

[r988]

Clutch judder is usually something like oil or some other crap somehow getting on the surface of the clutch itself and causing it to not grip properly or smoothly when engaging causing the juddering effect as it grips in part, then slips, then grips and so on.

It can also be caused by other parts of the clutch or flywheel being slightly out of shape usually from being just plain worn out or glazed to the point it's not getting consistent grip.

It's usually a sign your clutch/flywheel might need to be looked at/replaced at some point in the near future. If it's only minor or infrequent then it will likely not need urgent attention. In a newer car, or a make of car with a known problem in that area I would get it looked at sooner in case there is some underlying problem that is causing it.

If you are cheap and suspect it's only a glazed surface you can do the crude method of fixing it, which is to basically slip the clutch very savagely which might restore normal operation, but that's just delaying the inevitable. To do this you put the car in a high gear and rev the engine high then dump the clutch, keeping the throttle on full and a foot on the brake as well, basically try and do a static burnout, but in top gear so the clutch slips and burns for a few seconds and that might be enough to burn off some glazing on your clutch. Not exactly very good for the car though, and not something I would really recommend in most cases unless it's just an old £100 banger that you don't really care that much about

[mackie1]

Can't it also be caused by a buggered release bearing?

[Sam_68]

No, r998 has pretty much covered it - usually worn or contaminated clutch plate.

Normal symtom of a worn release bearing is a godawful noise when you depress the clutch pedal.

[trooperiziz]

Parkinsons.

[Fruitcake]

Strange, I never thought it was that serious. My Punto had it from 14,000 miles and i ran it to just under 44,000 miles and it never seemed to get any worse.

Thanks guys

[Trooper2]

Fruitcake said:

I had it in my old Punto now I get a bit of it every now and then in my current car and just want to know what causes it, basically.

Also, is it serious?

Cadence Clutching....

[rustybin]

Some cars are worse for it than others. Impreza's have a bit of a reputation for it as do Alfa 164's. Might be worth enquiring over at Jap Chat ( I am assuming it's the MX5?) as to whether they have a known propensity for it.

[ninjaboy]

My Bravo does it when cold, i had a master cylinder go and it contaminated the plate