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Discussion Starter #1
My clutch pedal has an annoying vibration noise at certain RPM or speeds. It goes away if I hold my foot against the side of the pedal (but who wants to do that!:() I converted from an automatic to a manual trans. When I got my pedals I got the shaft (long bolt), the pedals and the old pedal bushings which I replaced. Is there supposed to be a rubber bushing or something between the clutch pedal and the bracket that holds the pedals under the dash? I would think that could possibly eliminate the vibration noise. I've tried tightening the nut on the end of the pedal shaft but I don't think I should tighten it further.
 

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1967 Chevy II nova Hardtop
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Changing a cars transmission from an automatic to a manual is similar to an organ transplant. Sometimes the treatment is unsuccessful and not all therapies work. Have you considered an automotive psychologist? Nervous tics, sometimes called vibrations are common and are tough to diagnose. Quite often in these situations a throw out bearing or an unbalanced pressure plate and or flywheel will create mild rejection interpreted as a nervous tic. It is always good advice to consult a licensed professional. :D
 

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Discussion Starter #3
I did put in an inexpensive "made in China" clutch pressure plate & throwout bearing...:eek: that I got from Rock Auto. Perhaps that's creating an abnormal vibration. On the other hand there has to be some vibration with any machine. So, I was wondering if I got all the parts when I bought my clutch pedal & linkage. Maybe I'm missing a bushing or something that's supposed to dampen the vibration in the pedal. I'm not sure the Phoenix is willing yet to see a psychologist yet but sometimes I think it may be just what I need! :D
 

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There is a rubber bumper that the clutch pedal rests against. Should also have a return spring to hold it against the bumper.
click on link to see what it looks like, should be available locally. GM used the same one on lots of models.

http://www.classicindustries.com/search?q=g9296&y=1977&m=nova

Here is where it mounts

 

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Discussion Starter #6
Philip, I did get the bumper and also put in a retun spring that holds the pedal firmly against the bumper. That did help considerably from where it was back in the spring when I first got it on the road. But there is still an annoying vibration which seems like a back & forth movement rather than up and down movement. That's why I was wondering if maybe there is supposed to be a rubber spacer or gromet on the shaft to keep the pedal from vibrating against the bracket under the dash.

There is a rubber bumper that the clutch pedal rests against. Should also have a return spring to hold it against the bumper.
click on link to see what it looks like, should be available locally. GM used the same one on lots of models.

http://www.classicindustries.com/search?q=g9296&y=1977&m=nova

Here is where it mounts

 

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I remembered that conversation, did not realize it was done. Getting old has its drawbacks, especially on memory but I do get a discount at Denny's and the movie theater :D
With disc wear the free play needs to be adjusted. Maybe the vibration is from the throw out bearing slightly touching the pressure plate.
 

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Discussion Starter #8
I'll experiment with the clutch adjustment and see if that is the issue. Otherwise perhaps it is as Pragmatist suspects...my cheap & possibly unbalanced parts. My flywheel is an OEM unit they put on 67-69 Camaros that I found in the trunk of a 75 Nova. There isn't any abnormal vibration from the engine itself...just when I drive at certain speeds--consistently vibrates at freeway speeds.
 

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Discussion Starter #10
Isn't there supposed to be a shouldered bushing at the pedal pivot shaft?
That's what I'm wondering. I started with nothing so I don't have anything to compare to. Along with the pedals and clutch linkage there were only a few other parts. One was a hard plastic/nylon bushing (not the thin shaft bushings). I couldn't see a logical use for it at the time so I just put it in the spare parts pile.
 

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Discussion Starter #11
I'll experiment with the clutch adjustment and see if that is the issue. Otherwise perhaps it is as Pragmatist suspects...my cheap & possibly unbalanced parts. My flywheel is an OEM unit they put on 67-69 Camaros that I found in the trunk of a 75 Nova. There isn't any abnormal vibration from the engine itself...just when I drive at certain speeds--consistently vibrates at freeway speeds.
I did take it out yesterday. As usual, vibration noise from the pedal. I reached down with my hand. I could hardly feel the vibration with my hand. No visible movement. A very fine (high frequency?) vibration noise coming from up where the pedal butts up against the bracket that holds the pedals under the dash.
 

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I did take it out yesterday. As usual, vibration noise from the pedal. I reached down with my hand. I could hardly feel the vibration with my hand. No visible movement. A very fine (high frequency?) vibration noise coming from up where the pedal butts up against the bracket that holds the pedals under the dash.
Will that hard plastic/nylon bushing fit between the pedal and the bracket? If not I'd find one that will to isolate the two pieces and probably eliminate the issue.
 

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Discussion Starter #14
Theres 2 plastic bushings that go on shaft, the one that is in the pedal assembly. If there not in it could cause a vibration. Good Luck
I've got the thin ones that go between the pedal and the shaft where the pedal pivots. I put new ones in. Is there another bushing on the shaft that dampens vibration between the pedal and mounting bracket?
 

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There should also be a steel sleeve that goes in between the plastic bushings and the bolt. So from outside to inside it would be: Pedal tube, plastic bushings, steel sleeve, mounting bolt.
 
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