Hot Rod Forum banner

1 - 8 of 8 Posts

·
Registered
Joined
·
9 Posts
Discussion Starter #1
I swapped 350s on my 81 chevy 4x4 this weekend. When installed, the new engine started and ran great, until I stepped on the clutch. At this point it started to make a terrible squeel like a loose belt only 10 times worse. I let off the clutch and the noise was still there. I shut the truck down and started it back up and the noise was still there.

During the swap I had to change over the flywheel and clutch assembly to the new engine. The clutch is not very old and worked great with the old engine. Could I have assembled something wrong? The truck will not go into gear with the clutch pedal pushed in now either. I am pretty green when it comes to working on a clutch, so excuse me if I am being too vague? Any help would be appreciated. :confused:
 

·
Registered
Joined
·
237 Posts
In an effort to get more information - if you were to crawl under the truck (w/o it running) and have a buddy press the cluch pedal, can you see the pressure plate disengage the clutch disc?

This will require removing the lower cover if you have it on there.

Does the clutch make any racket with the engine off and you press it? Like maybe something is rubbing as it shouldn't.

BTW - are you certain that the new motor had a decent pilot bushing in the crank?
 

·
Registered
Joined
·
9 Posts
Discussion Starter #3
When I was underneath looking as someone pushed in the clutch pedal, it did not make any wierd noises. I did notice that the clutch fork rotated as it moved forward like it was binding on something. Is this normal?

I will check the pressure plate and disk tomorrow. I am not sure about the pilot bushing. The engine had a flex plate before if that matters.
 

·
Registered
Joined
·
237 Posts
Automatics do not use the pilot bushing - its just a little bronze bushing that is stuck in the back of the crankshaft. The input shaft of the transmission goes here and it supports that side of the shaft. What kind of clutch setup? Hydraulic, bell crank, cable??

Clutch forks are not supposed to rotate, it should just go forward and back (or vice versa, depending on your setup). I think you would be doing well to pull the transmission so you can get a look at the crankshaft and make sure it has a pilot bushing installed and you would also get to see what was rubbing to make that sound. If you don't have a pilot bushing, your transmission won't last very long.
 

·
Licenced Automotive Technician
Joined
·
1,625 Posts
you didn't happen to "hang" the trans before the bolts were in, did you? doesn't take much, and you bend the release "fingers" (for lack of a better word) on the bellville spring, making some higher/lower than others. this makes your release bearing contact unevenly. then when you step on the clutch, it may rotate a bit as the release bearing slides and contacts the lower fingers. bent fingers like this can cause an unholy ****ing racket of squealing, grinding, ect., and your clutch will not fully release, as only part of the pressure plate is having spring press. released.
 

·
Registered
Joined
·
9 Posts
Discussion Starter #8
I pulled the tranny from the engine tonight and found the release bearing mangled and in a few pieces. The fork has a deep groove on one of the ears also. The disk and pressure plate look fine to me, but that doesn't mean much. I am taking them in to get checked out by someone who knows what they are looking at tomorrow. Thanks for all the help.
 
1 - 8 of 8 Posts
Top