superloaf

Out of nowhere my 86 951 started squealing today. It's a very high pitched squealing, almost like a slipping belt, and it happens mostly at idle. Sounds a bit like light pressure on a spinning metal object; no heavy grinding. When I depress the clutch pedal it goes away. What is strange is that the noise stops before the clutch begins to move; in other words the noise is mostly gone when the slack in the clutch pedal is taken out and then completely gone within the first 5mm of clutch activation. If the car is revved it also seems to go away. Seems to be coming from front clutch area and not tranny.

I've read about all sorts of clutch sounds but not sure any are like mine. I just replaced the clutch slave cylinder, slave cylinder hose, and bled the system about 500 miles ago and no problems until now. Also, if car is not running, there is a slight noise when depressing clutch pedal, a similar squeak to the squealing but without the spinning action as would be expected in a non running car.

Any ideas?

Oh, clutch has about 150,000 miles on it (car has 200,000 with new clutch at 50k before i bought it and original torque tube) and last i measured, it was about at the end of its life so there's that to throw into the mix....

Dan Martinic

Hmm.. pilot bearing?

I recently did my clutch. Car has almost 160,000 miles. The clutch disk still measures half within spec; it's stamped "8.87". However, the throwout bearing suddenly got real loud at first pedal movement and sure enough it was near-seized when removed.

With careful driving, these clutch disks might last forever.. but.. there's all those other parts that just age. Time to pull the whole package!

superloaf

Dan Martinic

I bet you'd make your trip no worries if it were tomorrow. The only thing ever stopped me cold was a fuel pump. I drove on a bad throw-out bearing for longer than I care to admit; the parts there are pretty solid and the symptoms give lots of early warning.

Not sure about a "year or two" though lol! Start ordering parts now and maybe you'll beat the deep freeze of February (not fun wrenching in dead of winter--ask me how I know)

superloaf

Is that what it sounds like, a bad throw out bearing? (Is that the same as pilot bearing?)

Dan Martinic

When my throw-out bearing started going, it was an ugly spinning noise *upon initial clutch pedal movement*; that is, as you begin to push the pedal, the fork pushes the TOB against the pressure plate; since the PP is spinning, the TOB now spins. If the TOB is dodgy, it will make noise. If your pedal is adjusted properly, when your foot is off it, the TOB isn't spinning, and no noise no matter what the condition.

The pilot bearing, however, spins with the shaft inside the torque tube--even when your foot is off the pedal.

Either way, the car is telling you something's not right, and one day, that piece will fail. It's time