Wearing clutches

[sawood12]

Last time my car was in at the specialist he commented that the extension on my slave cylinder indicated that my clutch was pretty worn and probably not far of replacement. Since then i've been paying into my 'Clutch and Cylinder Head Gasket Replacement Fund' as I knew the bill when it comes will be a substantial one. However now i've got the cash sat in my little fund there is still no sign of my clutch slipping and the temptation to raid the fund for my long awaited and often delayed MAF kit purchase is very very nearly too much to resist any longer. However sods law says that if I were to raid the fund for my MAF kit the very next week my clutch will start slipping!! How much warning do the clutches on these cars give you before they totally give up?? I believe that the turbo clutches don't have the rubber damper mechanism that often fails on S2's so I imagine that the main need for clutch replacements on turbos is clutchplate wear which should give you plenty of warning before they completely give up the ghost.

I realise that this is something that is very difficult or even impossible to predict but is there a measurement I can take on the slave cylinder that indicates how much clutch friction material I have so I can estimate how many more miles I might have before replacement?? I'm not a heavy slipper of the clutch, I never (well almost never) do full clutch smoking take-offs, i'm am pretty slick at matching engine revs to road speed when changing down the box to minimise or even eliminate clutch slippage and I absolutely never ride the clutch on hills so I fancy my chances in buying time to replenish my clutch fund if there is some material left on the clutchplates.

 

[Fen]

The only 944 clutch I have ever had fail was an S2 one and it was the rubber centre that broke up. The Turbo clutch has springs as you say, but they can fail also.

In terms of wear I imagine it would just start to slip like any other car's clutch when it wears out. You would get some time with it slipping, but it's a bit of a "how long is a piece of string" to guess how long between noticing the slip and the car being undriveable.

 

[berg944]

Can I assume that a turbo clutch would slip (friction plate worn) mainly due to drop in pressure plate force?

If this is the case you would not cause any damage and would notice it "on boost" first and always get home.

If anybody can confirm that the friction plate disintegrates or goes to the metal than I would measure the wear by the gap in the inspection hole described in Clark's or it might cost you a flywheel.

Mike[:'(]

 

[Fen]

To be fair my Turbo clutch was doen to the rivets and scoring the flywheel with no signs of slipping when it was taken out.

 

[berg944]

Turbo clutch was doen to the rivets and scoring the flywheel with no signs of slipping when it was taken out.

Scott, I would measure the distance from the front edge of the inspection hole (edge closest to the front of the car) to the edge of the clutch slave cylinder piston, 18mm when new and 34+mm replace.

I measured mine the last time I went under the car and wrote it down so I can keep an eye on it, easier for me as I have no heat shield in the way........just realised that might be why my foot wells get very warm!

Mike

 

[sawood12]

Cheers Mike i'll do that. I suppose I can divide the percieved remainder material by the number of miles since the last clutch install to get a very rough idea as to how long i've got left.

 

[berg944]

Thats what I was thinking but I think it will wear more quickly as the plate gets thinner due to less spring pressure.

It should give you a very rough idea as it is how many times you use the clutch not miles.

 

[sawood12]

ORIGINAL: Fen

To be fair my Turbo clutch was doen to the rivets and scoring the flywheel with no signs of slipping when it was taken out.

Fen, I noticed yesterday that my clutch has what only can be described as a notchy feel at the top of the pedal movement just as the clutch fully engages. Did your clutch have this trait just before you replaced it??

 

[Fen]

I don't recall any clutch problems at all before it came out, it was only removed as the engine had to come out after holing the sump ona piece of debris on the road.