Noise in clutch (1 Viewer)

[Bertbj40]

Bj40 1979
I have a knocking sound when car is neutral and i don’t push the clutch pedal. When i push the clutch pedal sound goes away. What is broken?

 

[77mustard40]

It could be the throw out bearing, put the vehicle up on jack stands so it can't move and crawl under there and remove the cover. You should be able to see that is making the sound.

Sounds like its time for a clutch job.

 

[Bertbj40]

Cover?
Is that the plate with two bolts in? Engine side?

 

[Pighead]

Cover?
Is that the plate with two bolts in? Engine side?

Nope. in the middle, right behind the oil pan. might be held on with 5 or 6 slot screws, it'll be the lowest and oiliest pan-type thing behind the oil pan.

 

[3_puppies]

it's a B engine, I don't think they have the flywheel cover like the F engine

does the noise speed up with engine rpm? most likely due for a clutch job

 

[Pighead]

it's a B engine,

Ooops, missed that part...

 

[RWBeringer4x4]

My clutch/transmission has made a “chugging” noise while idling in neutral for about 8 years now... three years ago, I put in a new clutch, pressure plate, and throw out bearing and the noise persists.

The throw out bearing should be sitting still when the truck is in neutral. It shouldn’t be making any noise unless the clutch is out of adjustment and the bearing is “riding” the pressure plate as it spins. Otherwise, the bearing is only spinning when you step on the clutch - so if there is an issue this is usually when it would make noise.

The only thing I can figure is that the transmission input bearing is still spinning when the truck is in neutral - and there’s enough wear on it after 40 years that it makes some noise. I’m building a new transmission (very slowly) to go in - if the sound goes away I’ll know that was the culprit. Input bearing is arguably a worse issue to repair but depending on how bad the noise is it may go another decade like mine has...

 

[Bertbj40]

it's a B engine, I don't think they have the flywheel cover like the F engine

does the noise speed up with engine rpm? most likely due for a clutch job

Hey,

When i speed up, noise is gone. Or i can’t hear it anymore. I placed 4x4 box in neutral and gearbox in a gear and noise is the same for all the different gears

 

[Pighead]

Check the tension on your clutch return spring. I had a sorta similar noise that I finally figured out; my clutch return spring. at rest, was slack. Put in a slightly shorter spring, noise was gone.