Clutch Chatter
Thread Starter
Instructor
Joined: Jul 2017
Posts: 231
Likes: 15
Clutch Chatter
So I just got the nerve to take my new (to me) 1978 around the neighborhood. No plates, no registration and no mufflers, just someone who was dying to take it for a spin.
The car needs a lot of work, but I bought it from an engine performance shop who just rebuilt the motor, put in a new clutch and throw out bearing and fixed all the major mechanicals. I need to do the interior and body. I'll also have to fix the gremlins as they arise, like this one.
When I pull out in first, the clutch has a chatter. Same in reverse. I know that this typically means that the clutch is bad, but I know that it's new.
This guy did it right. Her found a slight crack in one of the heads and found a correct year matching head. He's a performance shop and all the work I see is top notch. He wouldn't have lied about a new clutch if there wasn't one.
Maybe it needs breaking in???
Here a pic of the engine compartment. He even put in a new radiator. I can't imagine he'd tell me he put in a new clutch if he didn't.
Thoughts?
PS, the test drive was SO MUCH FUN!!!
The car needs a lot of work, but I bought it from an engine performance shop who just rebuilt the motor, put in a new clutch and throw out bearing and fixed all the major mechanicals. I need to do the interior and body. I'll also have to fix the gremlins as they arise, like this one.
When I pull out in first, the clutch has a chatter. Same in reverse. I know that this typically means that the clutch is bad, but I know that it's new.
This guy did it right. Her found a slight crack in one of the heads and found a correct year matching head. He's a performance shop and all the work I see is top notch. He wouldn't have lied about a new clutch if there wasn't one.
Maybe it needs breaking in???
Here a pic of the engine compartment. He even put in a new radiator. I can't imagine he'd tell me he put in a new clutch if he didn't.
Thoughts?
PS, the test drive was SO MUCH FUN!!!
Melting Slicks
Joined: Dec 2000
Posts: 3,363
Likes: 303
From: Lansdale 19446 PA
2024 C3 of the Year Finalist- Unmodified
St. Jude Donor '10-'11, '15, '19
This may be a shot in the dark but it could be the flywheel. I got a 76 from my best friend and he had a new clutch installed. They never touched the flywheel when they installed the clutch.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
Thread Starter
Instructor
Joined: Jul 2017
Posts: 231
Likes: 15
This may be a shot in the dark but it could be the flywheel. I got a 76 from my best friend and he had a new clutch installed. They never touched the flywheel when they installed the clutch.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
Thanks!
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
This may be a shot in the dark but it could be the flywheel. I got a 76 from my best friend and he had a new clutch installed. They never touched the flywheel when they installed the clutch.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
I pulled the engine and trans that winter and looked at the flywheel when I separated the two. The flywheel had many cracks and "hot spots". Had it resurfaced and the chattering went away.
Talk to the shop, let them drive the car and witness the chatter, maybe you can get him to help you out. You don't know until you ask.
Melting Slicks
Joined: Dec 2000
Posts: 3,363
Likes: 303
From: Lansdale 19446 PA
2024 C3 of the Year Finalist- Unmodified
St. Jude Donor '10-'11, '15, '19
I drove the it from February until December without any further issues. In December, I backed it into the garage and pulled the engine/tranny and started the restoration.
Thread Starter
Instructor
Joined: Jul 2017
Posts: 231
Likes: 15
I was going to mention the flywheel as a possible problem, but the phrase - He's a performance shop and all the work I see is top notch, made me think it wasn't the case. Personally, I never install a clutch without the flywheel being new or resurfaced by the local machine shop.
Talk to the shop, let them drive the car and witness the chatter, maybe you can get him to help you out. You don't know until you ask.
Talk to the shop, let them drive the car and witness the chatter, maybe you can get him to help you out. You don't know until you ask.
Burning Brakes
Joined: Jan 2012
Posts: 943
Likes: 73
The email sounds better.
The last clutch chatter I had was in a 72 camaro I drove it for months that way, I sold the car without changing out the clutch and that guy sold it to another guy. So, you can drive it, but it will get worse and if you beat on it and it heats up, the front end shakes like it wants to come off (don't ask how I know).
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Pro
Joined: Oct 2000
Posts: 558
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From: Vancouver, B.C., Canada
My bet is either hotspots on the flywheel or a broken spring in the clutch disk. I've experienced both over the years. Either way i'ts probably gotta come out to fix. You'll only damage it more by driving it to much.
Thread Starter
Instructor
Joined: Jul 2017
Posts: 231
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Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
You are aware that the clutch DOES need to be driven in normal city traffic for several hundred miles....up to 500 miles easily. Chatter is NOT uncommon..and that also depends on how you are driving it and using the clutch. Don't baby the clutch but don't pound on it either. Press in on the pedal..shift and release the pedal. The slower you release the pedal the more you are screwing things up. And this also means I would not like for you to 'pop' the clutch all the time....like I wrote....drive it normally in the inner city. Try to stay away from HILLS where you have to let off and get going UP a hill.
I WOULD NOT worry about it at this point. With it being BRAND NEW...drive it and no crazy 'jack rabbit' stuff....or 'slipping' stuff.
OR...tear it all apart...and find that there was SOMETHING wrong or NOTHING wrong other thatn it was new with basically no miles on it.
DUB
I WOULD NOT worry about it at this point. With it being BRAND NEW...drive it and no crazy 'jack rabbit' stuff....or 'slipping' stuff.
OR...tear it all apart...and find that there was SOMETHING wrong or NOTHING wrong other thatn it was new with basically no miles on it.
DUB
Last edited by DUB; Aug 8, 2017 at 07:25 PM.
Thread Starter
Instructor
Joined: Jul 2017
Posts: 231
Likes: 15
You are aware that the clutch DOES need to be driven in normal city traffic for several hundred miles....up to 500 miles easily. Chatter is NOT uncommon..and that also depends on how you are driving it and using the clutch. Don't baby the clutch but don't pound on it either. Press in on the pedal..shift and release the pedal. The slower you release the pedal the more you are screwing things up. And this also means I would not like for you to 'pop' the clutch all the time....like I wrote....drive it normally in the inner city. Try to stay away from HILLS where you have to let off and get going UP a hill.
I WOULD NOT worry about it at this point. With it being BRAND NEW...drive it and no crazy 'jack rabbit' stuff....or 'slipping' stuff.
OR...tear it all apart...and find that there was SOMETHING wrong or NOTHING wrong other thatn it was new with basically no miles on it.
DUB
I WOULD NOT worry about it at this point. With it being BRAND NEW...drive it and no crazy 'jack rabbit' stuff....or 'slipping' stuff.
OR...tear it all apart...and find that there was SOMETHING wrong or NOTHING wrong other thatn it was new with basically no miles on it.
DUB
When I register it, I'm going to drive it like I stole it!
Last edited by Norcoastal; Aug 8, 2017 at 08:26 PM.
Race Director
Joined: Sep 2005
Posts: 18,640
Likes: 121
From: Farragut,TN
I was going to mention the flywheel as a possible problem, but the phrase - He's a performance shop and all the work I see is top notch, made me think it wasn't the case. Personally, I never install a clutch without the flywheel being new or resurfaced by the local machine shop.
Talk to the shop, let them drive the car and witness the chatter, maybe you can get him to help you out. You don't know until you ask.
Talk to the shop, let them drive the car and witness the chatter, maybe you can get him to help you out. You don't know until you ask.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
SERIOUSLY..I WOULD NOT do that with the clutch being NEW. give it the time it needs to seat properly.
The reason I am mention this is that when I do clutches for customers. They get the paperwork from the manufacturer that STATES what I wrote about the break-in period. And then I tell them numerous times verbally and also wrote it down on the invoice...and when they leave the shop and smoke the tires...what they did not realize is that they just voided the warranty.
I know how people want to run their cars hard at times..but there are times that IF a person wants a clutch to preform well and allow them to do this for a long period of time...the initial break in period is important and I am done trying to convey how important this is.
Hopefully the shop that did the work also checked the bore concentricity.
DUB
The reason I am mention this is that when I do clutches for customers. They get the paperwork from the manufacturer that STATES what I wrote about the break-in period. And then I tell them numerous times verbally and also wrote it down on the invoice...and when they leave the shop and smoke the tires...what they did not realize is that they just voided the warranty.
I know how people want to run their cars hard at times..but there are times that IF a person wants a clutch to preform well and allow them to do this for a long period of time...the initial break in period is important and I am done trying to convey how important this is.
Hopefully the shop that did the work also checked the bore concentricity.
DUB
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
DUB