I have a few other posts about this but this is a direct question for the clutch experts out there:
I have bad chatter on clutch release on start off, forward and reverse, in my 95 C4. I have tried both Spec stage one and Caroline clutch stage one. Full single mass and matching clutch etc setup. I did the last install myself and torqued everything to absolute spec. Why would two different full clutch kit have bad chatter on start off (big note here, I just bought this car needing clutch I was told so I dont know if it had chatter before) . There is not way to balance the single mass, I was told it would install only one way. I have been thinking internal transmission problems, but can any one give me possible causes for chatter besides clutch and flywheel? I have carefully bled the master and slave, but have both new on order eliminate them from the picture, but even it they were bad, they wouldn't cause a chatter...right? Just hard to shift or put in gear but no chatter. I am at a loss of ideas. Please help!

 

Did you install a new pilot bushing when you did the clutch change?

Did you make sure the mating surfaces of the FW and Disc were contamination free during installation, one greasy hand print will cause all kinds of chatter issues on a new set up?

Gibby

 

You did use the weight that came with the single mass flywheel correct? If not, you'll make short order of your main bearings.

Regarding chatter...how did you break it in? If you slipped the clutch a lot, that will result in resin on the flywheel and corresponding chatter. You have to drive pretty easy the first 500 or so miles. Single mass flywheels are also just a little more difficult to launch when you're used to the dual mass. Gotta rev the engine a bit more, or you'll get some chatter. Clutch master cylinder and slave cylinder have nothing to do with chatter...unless the slave is leaking fluid into the bellhousing.

 

Neither spec or Carolina clutch had any weights for flywheel. I asked them and they said it was already balanced . New pilot in both installs .

 

I have it too with the Spec II; alum. Fidanza FW, etc....You have a lighter FW and a grabby clutch.....it's going to chatter a bit...especially in reverse at times upon slipping it out.....very common

 

Yes, the flywheel is neutrally balanced. Unfortunately, the dual mass has a 30g offset weight. Therefore, if you installed a new flywheel in place of a dual mass, you Absolutely need weight installed. The weight is bolted in place. Sometimes they ship it loose in the box while other times it's already bolted to the flywheel (but the bolts should be verified to be tight!).

Back of SPEC flywheel showing where the weight goes:


Back of SPEC flywheel with the weight bolted in place:


30g cast in weight on the Dual Mass is circled:


If you don't have this weight installed and you did a straight dual mass replacement, it's time for the transmission to come back out or you will destroy the main bearings in short order.

 

That's exactly what the Flywheel I installed from CC looked like. had a huge bolt on weight like that

 

I am not sure if mine had it or not. I AM SURE it wasnt loose in the clutch kit box.

 

By pulling the inspection cover, you should be able to rotate the engine and verify the weight is present. If it is not, you need to pull the transmission and install it. I would not run the car until you know the weight is installed.

 

I verified the clutch kit I tool out (Spec stage 1) DID have the weights, I am pulling Carolina clutch today to verify it has weight installed. This is driving me crazy. If there are any experiences C4 clutch guys close to Birmingham, I will pay you yo verify my install.
Chris
corvette95@charter.net
Leeds, AL

 

Did you use a new pilot bushing?

Was the fit super tight?

Any noise?

Experienced similar problems and it turned out to be a cheap pilot bushing that wsa sized too tight shoulda checked it before it went in.

It wasnt a Vette setup but all the same far as the bushing and its purpose.
As you described tough getting into gear shift, etc. Eventually wore in but sure at some point will need a replacement. Shouldnt cause chatter though all it does is center the input shaft.

 

If you have the weight in place, and you installed a new pilot bushing, then could it be your driving style? It took me a bit to get used to the single mass flywheel. Need more revs and less slip or it will chatter. Have you tried adjusting your launch style?

 

I dont buy these mfr saying a single mass will chatter that is BS and unacceptable. There should be none.
Some say with break in miles they go away my experience has been once it chatters always and gets worse.

 

I guess I am a little confused at your problem; do you have chatter or vibration issues or both??

vibration: weight on the fw issue; balancing problem; you will notice this driving down the road in gear; the whole car will shake violently because the fw attached to the crankshaft is not balanced with the engine

chatter: could be a number of things depending on how bad the chatter is; my experience is a grabby clutch disk due to high friction material used in hi-perf applications....a little chatter can be acceptable in that situation...severe chatter is not acceptable....
usually your puck style disks will cause a good amount of chatter due to the super hi friction material they are made of ...........what exactly is the car doing upon pulling from a dead stop upon slipping out the clutch?? Is the same in reverse??

 

I have a 1995 White Coupe, six speed, base model, no engine modifications, 75,000 miles on the odometer. I bought it knowing I needed to install a clutch. I figured, "How tough could that be?" Well that was before I found out that you could no longer get a dual-mass flywheel. I bought a solid setup from Carolina Clutch. It had a heavy SPEC Flywheel. Had the flywheel balanced using my old unit as a base. First installation had so much clutch chatter that I had a terrible time even driving it. Talked to Tom at CC and sent entire unit back. They sent me my old flywheel back and new PP and clutch plate. The new clutch plate was different than the first one. I had the flywheel resurfaced and reinstalled. It was certainly better than after the first installation, but the clutch chatter is still unnerving. The car is no longer fun to drive. Sometimes the launch is smooth but most of the time it is jerky. POA. Backing up a small grade in reverse is horrible. I was looking at a Ram Dual Disc Clutch kit that changes the pull system to a push system. It claims smooth drivability which is what I want. Anyone have any experience with this unit. Other ideas are welcome. Going to start on it in November.

 

I still havent figured out out my chatter, Stage one - Both Spec Clutch and then swapped for Carolina Clutch, New pilot bearing, I dont get it, chatter -bad- on start off and reverse. I did everything to absolute book spec. I dont understand why so many people are having this trouble going from dual to single mass. Some people have no chatter so-most have a lot. I understand a little more noise from single mass, but my chatter is unacceptable. I have a fluted pilot bearing on order and was gonna try one more time. ANSWER ME THIS, this clutch has less than five miles on it (Carolina Single Mass) should I have it resurfaced? IF anyone with first hand experience with fixing this problem, PLEASE let me know, I havent driven my Vette in 6 months. corvette95@charter.net (95 LT1) 80k miles. BTW someone asked me in another thread if my flywheel had 30gram weights bolted to flywheel- yes it did. I was sure I had a bad transmission until I started reading all this.

 

Ok, i did same thing with spec 2+ when i got my car. The thing chattered at first because it is a completely different style of driving. It smoothed out and got easier but i had to put about 1500 miles on it. Now there is not chatter unless i mess up. I think you just are not use to the new driving style. I use to rev and let the speed catch the rpms, now i rev release little then once moving just dump the clutch. The rpms never go below 700. I would say there is nothing wrong. A dual mass is always going to be a smoother system when thats what the car was designed to do.

 

Thanks, but no, its much worse than that.

 

check your motor mounts too.

 

Corvette95; did you get the issue worked out? I was planning on a Carolina spec II my-self this spring...but now!