input bearing or pilot bearing?

89 MJ 4.0 Peugeot

Start up, scraping sound from the bellhousing area. Push in clutch, it goes away. I can drive it and shift, etc.

Pulled the tranny today and there is scrapes on the starter and spacer plate, maybe the noise? However if thats it, how come it goes away with the clutch depressed?

From searching it sounds like it might be the input bearing from the tranny, but it also seems to me that if someone shoved the tranny in wrong last time it could have messed up the pilot bearing and also account for the spacer plate being bent into the flywheel. I don't want to reconnect all the BS until I try to figure this out first. What would go away with the clutch pedal pushed in?

If it is the input bearing do you have to open the tranny to get to it.

Thanks a bunch

I currently have the same problem right now...I am taking it to a shop so if you have time to wait I can get back to you

doug:repair:

The pilot bearing starts to turn when the clutch is disengaged. The input bearing stops turning when the clutch is disengaged.

I'm not sure how the throwout bearing in this model works, but some designs keep the throwout bearing lightly engaged all the time. If this is the case, then a noisy throwout bearing can go quieter when you push the clutch pedal, but the change should occur as soon as you put pressure on it, and not wait until the input shaft stops turning.

From what I've found (in general...)

If you get a bearing rattle with the clutch pedal down, think about replacing the T/O bearing.

If you get a bearing rattle with the clutch pedal up, think about replacing your input bearing and pilot bearing/bushing. If you've got a Peugeot, think about just sourcing a replacement AX-15 or NV3550. (If external slave, you'll have to change your master cylinder as well - but it's worth it.)

I vote throw-out if the noise stopps immediately after pushing the clutch, tranny input if it takes some time after pushing the clutch.

I thought that when the clutch is in (or on the floor if you will), the pilot bearing is not moving, as the input shaft is rotating at the engine RPM (but the tranny input and throw-out bearing ARE moving).


Edit:
And if you do put the peugeot back in, I would just get a new clutch slave cylinder while you have the thing out. Murphy's law only gives you a couple of weeks on that sucker if you put the original one back in.

TheNerd said:

I vote throw-out if the noise stopps immediately after pushing the clutch, tranny input if it takes some time after pushing the clutch.

I thought that when the clutch is in (or on the floor if you will), the pilot bearing is not moving, as the input shaft is rotating at the engine RPM (but the tranny input and throw-out bearing ARE moving).


Edit:
And if you do put the peugeot back in, I would just get a new clutch slave cylinder while you have the thing out. Murphy's law only gives you a couple of weeks on that sucker if you put the original one back in.

Click to expand...

When clutch is engaged, input shaft rotates at same speed as flywheel, so the pilot bearing is not turning. When you disengage the clutch, the input shaft of the transmission stops turning. Or it ought to.

It's the throwout!!:doh: The input shaft sits inside the pilot, and the throwout slides along the input shaft. Pilot can fail just as easy as the throwout but the described symptom points toward the throwout!!eace:

you guys rock. I felt the pilot bearing and it doesn't turn too easy, any advice on pulling the old one out? Haynes says pack it with heavy grease and stick a bolt in.

I used a Dremel with a "spiral" bit, and just cut a groove most of the way through the bearing. One good whack with a hammer/chisel, and the bearing finsihed splitting, then came right out. Or you could just go rent/borrow a puller...