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[C2] Chirp/whistle when releasing clutch

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Old 04-15-2019, 12:59 AM
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jsans
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Default Chirp/whistle when releasing clutch

Took the 65 out for a ride yesterday. (I have a manual 4 speed muncie trans)

I noticed a a whistling chirp sound towards the end of the clutch pedal release, almost every time and on any gear. I'm certain it's not coming from the clutch pedal itself. It''s fairly loud, but very brief. I'm wondering if the clutch is starting to go.
Old 04-15-2019, 01:07 AM
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ghostrider20
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The noise is made when you push the pedal to the floor?
Old 04-15-2019, 01:22 AM
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jsans
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No, as the pedal is coming up from the floor towards the end of its travel.
Old 04-15-2019, 04:30 AM
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856666
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With the engine off, press the clutch pedal down and release it - do you hear the noise?

If no - I would lean towards throw out bearing
If yes - I would check linkages

Phil

Last edited by 856666; 04-15-2019 at 06:35 AM.
Old 04-15-2019, 06:32 AM
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Frankie the Fink
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I would guess linkage, but do the test suggested above...
There are nylon bushings on the pedal horizontal rods in the pedal support that can deteriorate or are missing altogether. Make sure there is no side-to-side movement in the clutch pedal.

Last edited by Frankie the Fink; 04-15-2019 at 06:33 AM.
Old 04-15-2019, 06:54 AM
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65GGvert
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Engine running in neutral, does it continue to squeal with the clutch out and stop when you put a little pressure in on the clutch pedal? Sounds just like a throwout bearing to me.
Old 04-15-2019, 07:07 AM
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Frankie the Fink
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I would agree if it was a whirring or grinding sound, but not a chirp, but we'll see..
Old 04-15-2019, 11:32 PM
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jsans
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Phil, no. Do you know where is the throw out bearing is located?

Originally Posted by 856666
With the engine off, press the clutch pedal down and release it - do you hear the noise?

If no - I would lean towards throw out bearing
If yes - I would check linkages

Phil
Old 04-15-2019, 11:37 PM
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jsans
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Frankie,

Clutch pedal appears good. When driving, it sounds like the sound is coming from the outside, underneath the car. Thanks for helping.

Originally Posted by Frankie the Fink
I would guess linkage, but do the test suggested above...
There are nylon bushings on the pedal horizontal rods in the pedal support that can deteriorate or are missing altogether. Make sure there is no side-to-side movement in the clutch pedal.
Old 04-15-2019, 11:37 PM
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jsans
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I'll give it a try tomorrow.

Originally Posted by 65GGvert
Engine running in neutral, does it continue to squeal with the clutch out and stop when you put a little pressure in on the clutch pedal? Sounds just like a throwout bearing to me.
Old 04-15-2019, 11:38 PM
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Maybe I can record the sound.

Originally Posted by Frankie the Fink
I would agree if it was a whirring or grinding sound, but not a chirp, but we'll see..
Old 04-16-2019, 12:37 AM
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65GGvert
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Originally Posted by jsans
Phil, no. Do you know where is the throw out bearing is located?
It is mounted between the fingers of the clutch fork and butts up against the fingers on the pressure plate fingers. It goes around the transmission input shaft so the transmission has to come out to replace it. If you didn't already know where it is, you need to get someone who has changed one in a C2 before to do it or assist you. It is not a quick and easy job. It requires extra work because of the limited room due to the frame crossmember location. Many pull the engine and transmission together, either way you want to do everything right the first time, so that it doesn't all have to come out again.

It looks like this one:


Old 04-16-2019, 01:07 AM
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I'm guessing this might be the issue.

I'm wondering if I can make it to the winter, which is when I plan on dropping the original engine back into the car. The clutch still works perfectly with the exception of the sound.

Which maybe would be a good time to look at all the clutch components since everything would be apart anyhow. At that time, would it also be a good time to inspect ore rebuild the Muncie trans?



QUOTE=65GGvert;1599234853]It is mounted between the fingers of the clutch fork and butts up against the fingers on the pressure plate fingers. It goes around the transmission input shaft so the transmission has to come out to replace it. If you didn't already know where it is, you need to get someone who has changed one in a C2 before to do it or assist you. It is not a quick and easy job. It requires extra work because of the limited room due to the frame crossmember location. Many pull the engine and transmission together, either way you want to do everything right the first time, so that it doesn't all have to come out again.

It looks like this one:

[/QUOTE]

Last edited by jsans; 04-16-2019 at 01:08 AM. Reason: edit
Old 04-16-2019, 02:01 AM
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They usually make squealing noises for quite a while before anything serious happens. If pushing in a little on the clutch stops the noise. I think it's the bearing.
Old 04-16-2019, 04:25 AM
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[QUOTE=jsans;1599234896]I'm guessing this might be the issue.

I'm wondering if I can make it to the winter, which is when I plan on dropping the original engine back into the car. The clutch still works perfectly with the exception of the sound. Which maybe would be a good time to look at all the clutch components since everything would be apart anyhow. At that time, would it also be a good time to inspect ore rebuild the Muncie trans?

Hi jsans,

I agree with GGvert, the bearing will progressively make more noise but it will take some time for it to fail completely. Remember that the bearing is only working when you press the clutch pedal down, and these cars are not daily drivers, so it will last some time. If your Muncie is working fine there is no reason to mess with it other than new fluid.

Here is a tread with excellent pictures of flywheel, pressure plate, clutch disk and throwout bearing

https://www.corvetteforum.com/forums...h-chatter.html

Phil

Last edited by 856666; 04-16-2019 at 04:26 AM.
Old 04-16-2019, 11:15 AM
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I wouldn't push it IMO...
But you can always learn "rev matching"; e.g. "shifting without the clutch" ...
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Old 04-16-2019, 11:22 AM
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A chirping throwout bearing can last for years. A grinding one, not so much. It may get worse or better, especially with different temperatures. It's embarrassing to pull into a crowd of car guys with a chirping bearing though.

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Old 04-16-2019, 02:45 PM
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I'm thinking just replace the entire clutch if I can get a deal on one, since it's never been in the 30 years that I've had the car. Does this look like a good deal? This is local to me.

https://chicago.craigslist.org/nwc/p...863219149.html
Old 04-16-2019, 03:17 PM
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leif.anderson93
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Originally Posted by jsans
I'm thinking just replace the entire clutch if I can get a deal on one, since it's never been in the 30 years that I've had the car. Does this look like a good deal? This is local to me.

https://chicago.craigslist.org/nwc/p...863219149.html
John,
You don't need all that. Your flywheel should be fine and I recommend that you always use your original flywheel if possible. Your mechanic will know if it needs minor resurfacing. For $79.99 Rock Auto has a complete Luk clutch kit including a brass pilot bushing (which should be replaced while your mechanic is in there).
https://www.rockauto.com/en/moreinfo...321377&jsn=502
Old 04-16-2019, 03:43 PM
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Originally Posted by jsans
I'm thinking just replace the entire clutch if I can get a deal on one, since it's never been in the 30 years that I've had the car. Does this look like a good deal? This is local to me.

https://chicago.craigslist.org/nwc/p...863219149.html
All that work and to replace your bearing with somebody's junk. I would not go that route. I would install a new bearing, plate and clutch. If you are interested in a soft clutch, maybe I can find my receipts.


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