Clutch not disengaging
Thread Starter
Intermediate
Joined: Jul 2004
Posts: 38
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Clutch not disengaging
Been having trouble with the clutch not disengaging at high RPMs.... soo.... we get under there and try to bleed it. No luck, car now appears to have a problem getting into gear at any RPM.
To test it I put it in first, started the car, and on a flat surface had no brake and the clutch pushed all the way in. It tried to drive away. So, the clutch is clearly not disengaging all the way.
We pull the tranny/torque tube and put the spacer in for the clutch to see if that helps. No luck with that either.
Continue to bleed the clutch over the next 4-5 hours without any change. In order to get it into any gear I have to double clutch/rev match. At a stop it's almost impossible to get into any gear so I usually just turn the car off, put it in gear, and start it to get moving again.
Anyone have any ideas of what left to try?
Car's got cam/headers/Spec 3 clutch and a new slave cylinder (replaced during clutch swap)
To test it I put it in first, started the car, and on a flat surface had no brake and the clutch pushed all the way in. It tried to drive away. So, the clutch is clearly not disengaging all the way.
We pull the tranny/torque tube and put the spacer in for the clutch to see if that helps. No luck with that either.
Continue to bleed the clutch over the next 4-5 hours without any change. In order to get it into any gear I have to double clutch/rev match. At a stop it's almost impossible to get into any gear so I usually just turn the car off, put it in gear, and start it to get moving again.
Anyone have any ideas of what left to try?
Car's got cam/headers/Spec 3 clutch and a new slave cylinder (replaced during clutch swap)
Instructor
Joined: Aug 2004
Posts: 244
Likes: 0
Maybe the Master? Or blockage in the line. I would have put a new master in as well, its fairly easy if you go through the fenderwell. I think they say anything beyond the spec I, they recomend a revised z06 master/slave. I did a spec II with all new hydralics w/spacer and it works great. Maybe you got a bad slave. It should all work fine.
Safety Car
Joined: May 2003
Posts: 3,583
Likes: 14
From: Everywhere
You did replace the pilot bearing too? If it is bad it will turn your torque tube shaft also and make it seem that the clutch isn't disengaging. The disk is in the right direction? Did you also replace the flywheel? Mine was warped concave. I also have a Spec stage 4 with aluminum flywheel. No spacer and Z06 hydraulics. No problems. If you get under the car, NOT RUNNING, when someone steps on the clutch, you should see the pressure plate releasing and a slight gap open up between the clutch disk and flywheel. You should also be able to turn the disk with your fingertips when its disengaged also. I performed these tests with just the torque tube installed to make sure I didn't need the slave shim. I also test ran it up thru the RPMs to make sure I didn't have a vibration issue also before I put the car back together. 
Thread Starter
Intermediate
Joined: Jul 2004
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I doubt there's a blockage in the line, we bled thru an entire bottle of fluid just to make sure.... not saying there isn't one, but I certainly hope not.
The possibility may be that the master isn't able to keep up with the required hydraulics... but I hope that's not the case because I don't really want to go back thru and replace that as well.
Yes, we replaced the pilot bearing, and I didn't replace the flywheel, but I did have it turned/tested at a local machine shop.
The possibility may be that the master isn't able to keep up with the required hydraulics... but I hope that's not the case because I don't really want to go back thru and replace that as well.
Yes, we replaced the pilot bearing, and I didn't replace the flywheel, but I did have it turned/tested at a local machine shop.
Thread Starter
Intermediate
Joined: Jul 2004
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Originally Posted by eRiCdWoNg
Did you change the slave cylinder? I had mine fail on me.
I should get the Ram adjustable master cylinder tomorrow morning (yay for overnight shipping) and go from there.
Thread Starter
Intermediate
Joined: Jul 2004
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So, as an update. Slapped in the new Ram adjustable master cylinder and same problem. Tried adjusting it to see if that would help, and it didn't. 
So, the only thing I'm able to come up with at this point is that the flywheel was shaved too far and needs to either be shimmed, or replaced.
Has no one else ever had this problem?
Anyone know if you can shim these flywheels? So it looks like I've got to pull it all back apart (this would be the 4th or 5th time)
So, the only thing I'm able to come up with at this point is that the flywheel was shaved too far and needs to either be shimmed, or replaced.
Has no one else ever had this problem?
Anyone know if you can shim these flywheels? So it looks like I've got to pull it all back apart (this would be the 4th or 5th time)
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Racer
Joined: Aug 2004
Posts: 390
Likes: 0
From: Calera Alabama
I have the same problem and have gone through the same methods you have. I have a 99 coupe that I put a Z06 clutch in. I bought new everything. Worked great for about 7k miles, and than these problems. Replaced the slave, installed an adjustable master cylinder and still the problems. I have come to the conclusion that the pressure plate must be a POS and that is the problem. I have been so frustrated with it that I haven’t bought a new clutch yet. But the weather is starting to change my mind. And for the record I babied it for about 1k of those miles and there were no track runs on it. I was planning to get a Vararam and some headers before I took it back. Trust me I understand your pain. Just my dealings but I have had three friends that all have had SPEC’s in their F bodys and all have been terrible. But I have read that some people have them and are very pleased. I am ether going back with a Z06 unit or a RAM. Just my 2 cents. Please keep me updated so that I my no the best path to take and I hope you get her back up and going ASAP
Melting Slicks
Joined: Jun 2004
Posts: 2,836
Likes: 110
From: El Paso TX.
Any updates? I just put a new clutch in mine and it is doing the exact same thing. i just ordered the mcleod adjustable master and see if it works. same thing happen to my budies car and this cured it. Believe me i feel your frustration.
Thread Starter
Intermediate
Joined: Jul 2004
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Yea, so it's back working.
After a lot of reading and talking to people the flywheel, if turned to anything less than a thickness of 800 is unable to be used. Mine is currently 791. I had already installed the 055 spacer in the slave cylinder. The adjustable master helps to compensate for the "extra" thickness since stock thickness is 815.
To make a long story short, the problem did lie in the pressure plate. I did not replace the flywheel, and the car drives just fine. The pressure plate itself wasn't torqued down, which was pushing the plate away from the flywheel whenever the pedal was depressed. Went in, tightened the pressure plate, and all is well. :o
After a lot of reading and talking to people the flywheel, if turned to anything less than a thickness of 800 is unable to be used. Mine is currently 791. I had already installed the 055 spacer in the slave cylinder. The adjustable master helps to compensate for the "extra" thickness since stock thickness is 815.
To make a long story short, the problem did lie in the pressure plate. I did not replace the flywheel, and the car drives just fine. The pressure plate itself wasn't torqued down, which was pushing the plate away from the flywheel whenever the pedal was depressed. Went in, tightened the pressure plate, and all is well. :o
