Restored Camaro 396 M21 with 11 Clutch. New Flywheel, New Hays Diaphragm clutch, PP and TOB. Rebuilt M21 with new pilot bushing in the crank shaft. Everything is brand new......
When I touch the clutch pedal the clutch starts to squeal and as I depress the pedal to the floor the squeal continues. If I adjust the arm to where there is over 1 inch of free play and my foot is off the pedal the squeal stops. ( I run about 1/2 inch of play normally) Could I have a bad "new" TOB??? Or Tranny Problem???? Just trying to do some Diagnosis prior to taking the car apart.
Thanks Team Camaro

Restored Camaro 396 M21 with 11 Clutch. New Flywheel, New Hays Diaphragm clutch, PP and TOB. Rebuilt M21 with new pilot bushing in the crank shaft. Everything is brand new......
When I touch the clutch pedal the clutch starts to squeal and as I depress the pedal to the floor the squeal continues. If I adjust the arm to where there is over 1 inch of free play and my foot is off the pedal the squeal stops. ( I run about 1/2 inch of play normally) Could I have a bad "new" TOB??? Or Tranny Problem???? Just trying to do some Diagnosis prior to taking the car apart.
Thanks Team Camaro


It does sound like a bad throw out bearing but you said it was brand new? While I haven't seen a brand new one bad off the shelf, it is possible. Since the T/O bearing doesn't start spinning until you depress the pedal(assuming it is adjusted correctly), it makes sense that a bad one would make noise as soon as you depress the pedal. I hate to say it but it sounds like the tranny has to come back out. :(



Richard
Tech Support

I haven't seen one bad right off the shelf either, but...

The "best" one is all steel with a red seal,and has "BCA" and a number stamped on it.
There are a couple of others, one is just plain loose, even new, and another is half black plastic!

All are sold by the same part number, often in a timkin box.

Once, I accidentally ordered an olds throwout bearing from summit. This thing made a TON of noise with any pressure on the clutch pedal. This this was just plain bigger than one for a chevy, it didn't fit right.

A spun pilot bushing will have an intermittent squeal when the clutch pedal is pressed down.

Cheap Chinese pilot bushings have been showing up in auto parts stores that are slightly oversize and adulterated with iron. When you drive one of these oversize bushings into the crankshaft pilot hole, it will shave the outside edge and distort the inside diameter of the junk pilot bushing. It doesn’t take long for them to fail. This is why you should only use a “Made in USA” 100% bronze oilite pilot bushing. The rule for pilot bushings is “if a magnet will stick to it, don’t use it”.

It's the throwout bearing for whatever reason. Bad or improper adjustment. 1/2 inch of freeplay might be too tight. I run mine at 1".

thats what mine was doing...bad throw out bearing

Thanks, After some research I have found that most pilot bushings are not Oilite. Very surprising....NAPA sells the Oilite bushing and a roller bearing bushing. Any recommendations on the rollerbearing?
The clutch assy.... PP, disk and TOB are being returned to Jegs for replacement under warranty. If I am going to go to the trouble to take the car apart I am going to replace the clutch assembly while the parts are under warranty. I will inspect the TOB very closely prior to installation.

Is there a special technique for removing the old Pilot bushing from the crankshaft?

Thanks Team Camaro....A wealth of knowledge and support is awsome.

Thanks Rex,

I use grease and a bolt that is very close to the inside diameter of the pilot bushing. Just pump the hole full of grease and then pound it in with a hammer. Sometimes you have to keep adding grease but it will eventually start pushing the bushing out. They also make a tool for this but the grease is cheaper.