squeal on start up

Yeti's280zxt said:

I would think the squealing would be the T/O bearing. But it could also be the pivot joint on the clutch fork. Or the clutch pedal linkage.

The pilot bushing is just a brass sleeve and I don't think it could squeal because it is oil impregnated and not just regular brass.

The T/O bearing is only used when the clutch is depressed so that makes sense but the pilot bushing is always in use so the squealing would be happening all of the time.

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Uh, no.

Correct: The T/O Bearing will make noise when it's used---when the clutch pedal is depressed.

Incorrect: Anything said about the pilot bearing.

The Pilot Bearing has no speed differential when the clutch is engaged. The only time it can make noise or vibrate is when the clutch is disengaged and the flywheel and input shaft are turning a different speeds. It will not usually make a high pitched squeal. Generally it will gob up and manifest itself through difficult gear engagement and vibration---almost similar to a dragging clutch.

The only time the pilot bearing is working is the SAME time the T/O bearing is working. The way to separate the two is put a slight load on the clutch pedal so the clutch is not really slipping, and see if it squeals---if it does than it's the T/O bearing.

Another way to separate the pilot bearing from TO Bearing is on a downshift or when revving the engine (or not) after a significant gear change. Like from 5th to 1st without changing the engine speed to match. Usually you will hear the thing groaning. But the load check is probably a bit more precise.