1993 clutch/flywheel replacement
Melting Slicks
Joined: Jul 1999
Posts: 3,214
Likes: 101
From: Decatur, Alabama
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
Well 20 hours later and the clutch is in but doesnt seem to be releasing all the way. It won't go into gear when running. I can put it in gear with engine off, start it up and move fine, but it won't shift. Any ideas? We're going to try bleeding the clutch system right now. The pedal feels a little soft
Melting Slicks
Joined: Jul 1999
Posts: 3,214
Likes: 101
From: Decatur, Alabama
Dang, that's the problem I am going through with my third brand of clutch. I am going to replace the master and slave next and make sure it is bleed all the way. Very hard to bleed the system. I also found out on my first install the alignment took isn't once and done, the pressure plate and clutch can fall out of alignment with the tool still installed. Also the clutch fork ball locking screw spec is WRONG in manual, it's 10lbs per Bill at zfdoc.com
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
Well i didnt have a problem with the tool, the transmission slipped right in, easier then the richmond 5 speed on my '81. I'm thinking he has either a bad slave or master, and the original smoked clutch was a result of the failed hydraulic part. When i say this clutch was smoked, i mean smoked.
Melting Slicks
Joined: Jul 1999
Posts: 3,214
Likes: 101
From: Decatur, Alabama
Yeah. I would absolutely rule out slave / master first. When I talked to bill at zfdoc he gave me the name and number to the ONLY guy that sells both that he has his ow
Design and is better than new gm and better than All the after
Markets. He requires you to use only that set over anything else you can buy to keep his new transmission (which I have on order ) under warranty. I will find his name and number and post shortly.
Design and is better than new gm and better than All the after
Markets. He requires you to use only that set over anything else you can buy to keep his new transmission (which I have on order ) under warranty. I will find his name and number and post shortly.
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
Thanks
Is the fork pivot ball adjust able on these? My brother removed it to clean the bellhousing, and i asked him if he counted the turns when he took it out, and he said it was bottomed out. I didn't see any5hing about it being adjustable in the GM service manual, so i bottomed it back out like he said.
Is the fork pivot ball adjust able on these? My brother removed it to clean the bellhousing, and i asked him if he counted the turns when he took it out, and he said it was bottomed out. I didn't see any5hing about it being adjustable in the GM service manual, so i bottomed it back out like he said.
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
well i did torque it down per the repair manual so I should be ok then. and the manual says 11ft lbs for the locking screw, I doubt the extra pound is a big deal.
After trying to bleed 2 big bottles of clutch fluid through the system, the fluid was still coming out black. we removed the reservoir and found some some thick black substance on the bottom of it. my guess is one of the seals in the slave or master disintegrated. We're going to replace the slave and master. I want to replace the braided line also, is there anywhere to buy it from?
After trying to bleed 2 big bottles of clutch fluid through the system, the fluid was still coming out black. we removed the reservoir and found some some thick black substance on the bottom of it. my guess is one of the seals in the slave or master disintegrated. We're going to replace the slave and master. I want to replace the braided line also, is there anywhere to buy it from?
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Drifting
Joined: May 2007
Posts: 1,426
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From: Motor City
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
So the new master and slave went in today. Same problem only a little better, now I can force it into all forward gears, but not reverse. the clutch pedal feels soft to me still. Is there a special procedure I need to follow to get this system bled properly? Air in the system is the only thing I can think of at this point, other then the parts from Carolina Clutch are either wrong or just plain garbage.
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
ok,doing some research I read the slave cylinder for a '93 Corvette has the bleeder on the BOTTOM? Is this true? both the slave cylinder that we took out and the replacement cylinder have the bleeder at the 10:00 position. are these wrong? could this be the problem?
Drifting
Joined: May 2007
Posts: 1,426
Likes: 165
From: Motor City
If I remember correctly, the bleed valve is facing straight down on my 93, someone else can chime in on that one to confirm.
As far as getting air out of the system, reverse bleeding from the slave in the best method for getting all the air out. There are other methods that work, but to me this is the easiest and most effective. When I installed mine (both slave and master) dry and reverse bled from the bottom it worked great after one try. Nice firm pedal.
As far as getting air out of the system, reverse bleeding from the slave in the best method for getting all the air out. There are other methods that work, but to me this is the easiest and most effective. When I installed mine (both slave and master) dry and reverse bled from the bottom it worked great after one try. Nice firm pedal.
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
i called my brother this morning and told him to unbolt the slave, spin it 180*, bolt it back in, and then pump the pedal until it feels firm. hopefully this will fix the problem
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
So he turned the slave 180* but no luck, it's still not disengaging all the way. He said the braided line is at the 1:00 position and the bleeder is at 6:00 now. I think it's the wrong slave.
Melting Slicks
Joined: Dec 1999
Posts: 2,816
Likes: 2
From: Austin, TX
This is the best reference I've seen for ZF clutch maint / bleeding procedures.
http://www.zfdoc.com/clutch_hydraulic.htm
http://www.zfdoc.com/clutch_hydraulic.htm
Advanced
Joined: Dec 2001
Posts: 85
Likes: 0
From: Washington PA
Replaced my clutch with one from Carolina Clutch. I too had a problem with putting the transmission in gear. My problem was I used too much Lock tight on the pressure plate bolts when I put them onto the flywheel. It glued the clutch plate to the flywheel just enough to keep it spinning and not be able to it into gear. I too though the problem was in the hydraulics but it was not the problem. I am not happy with the operation of the Single Mass Flywheel. It is jerky and unpredictable as to get a smooth launch from stop. Once it is moving it is okay. Reverse moving up a grade is a real experience. The car is now no longer fun to drive. GM used a Dual Mass Flywheel for a reason. Too bad we can no long get them.
Thread Starter
Le Mans Master
Joined: Feb 2011
Posts: 5,943
Likes: 61
From: Southern NH
wow, that could definitely be my problem. I made sure I used a good amount of loctite on the bolts.
I don't understand how loctite can be that strong though. I would think the bond would break the first time the engine was started.
I don't understand how loctite can be that strong though. I would think the bond would break the first time the engine was started.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Assuming the slave was correctly bled and it's the right part number, you have one or more of the following wrong...
- Incorrect or incorrectly installed throwout bearing
- Bent clutch fork
- Incorrect flywheel thickness
- clutch plate installed incorrectly
If you look closely at the pic, you can see where it is labeled "Flywheel Side"...
The slave is self bleeding with enough pedal pumps, so that should be fine by now. That leaves the throwout bearing and the clutch fork as the likely culprits. I suppose there's an outside chance the new slave cylinder is bad. There was a run of them that had incorrectly installed seals. If you have a bad one, you should have a fluid leak which you would see when you remove the slave from the bellhousing.
Your brother should also compare the old slave to the new one to ensure the have the same rod length.
Last edited by 96GS#007; Aug 23, 2012 at 11:17 PM.