When I put my 98 6 speed away the other day the clutch didn't disengage until I had the pedal all the way to the floor. It did that about five times and I got the car in the garage I checked the fluid level and it was full. I looked under the dash and jacked up the car and found no obvious leaks. I let it sit for a while, pumped the pedal a few times and it went back to normal. I have driven it about 40 miles since and it appears to be ok. Any suggestions? Also is bleading the clutch as much of a job as the book says?

 

Bleeding sux. Have fun i'm going thourgh the same BS. You got to love this clutch system my 1987 acura clutch system was better.

 

Pray it's the clutch master cylinder warning you. It's an afternoon job to replace.
Pray hard.

 

I think we have the same problem. A year ago I parked the car in the driveway facing down hill and left the car in reverse. After shutting off the engine and letting out the clutch, it did something when rolling forward a bit. Later, I could not get it out of gear with the engine running. It went away after pumping the clutch and reving the engine.

It happened again a few months later and now, 14 months later, it's back pretty much all the time. The problem went away completely on Sunday and last night I left car in reverse as I was backing up the driveway and deja vu, it happened again.

The pressure plate on C5 Z06 is self adjusting to compensate for disc wear. I believe one on the 3 spring loaded wedges on the back side of the pressure plate might be the fault. You might be able to do something working thru the inspection cover.

It's at the shop now getting a new flywheel, pressure plate, disc, slave/ throwout bearing and master cylinder. I will post more after I do autopsy on pressure plate.

I can't complain as the car has seen 8 years of track time events.

 

I don't mind attempting this myself but don't have access to a lift so I would have to deal with the hassle of jacking it up real high. I was wondering what the cost of this clutch replacement is going through a shop? Can you give me a ball park number if you don't mind?

 

I paid $1,190 for labor and $826 for parts which included flywheel, pressure plate, disc, flywheel bearing, slave/throwout bearing and clutch master cylinder. Parts were discounted by $291.

I just got car back tonight. All the parts looked good with the exception of the pressure plate. It had one of the 12 tabs broken off. The 3 self adjusting ramps/cams looks OK. The flywheel surface still had all the machining marks on it after 8 seasons of HPDE and 30,000 miles!

 

Not saying this is your problem, but the C5's have been known to have a problem with a sticky clutch when the Hydraulic clutch fluid gets old/turns black.

Unless you've modified the "Slave Cylinder" by adding a "Hydraulic Fluid Bleeder Line" to the top of the "Slave Cylinder you'll have to use the old "Turkey Baster" to suck out the old brake fluid from the Brake Master Cylinder; then refill master cylinder with clean fluid; replace the master cylinder cap, then pump the clutch pedal 50 or 60 times. Repeat these steps about four or five time or until the fluid in the brake fluid in the
master cyline stays clean (or pretty clean). Yeah, it's a pain in the butt, but it works. Then test drive your car. . . see if the clutch works properly. If not repeat steps above a few more times. Then drive the car again and test clutch action.

Or you could take your Vette to a garage/dealer and have them do the work. Just check the fluid to make sure its clean before you drive the car away from the garage/dealer.

 

You do know that the clutch and brakes have different master cylinders.....right?

 

Yeah you're right. . . I must have had a "Senior Moment" when I was typing my post. Thanks for pointing that out. I should have said "Clutch Master Cylinder" not the "Brake Maste Cylinder".

 

What fluid is the best to use??

 

If this is the first time you are changing it you might want to stick to the GM fluid. It's overpriced and difficult to find but is compatible.

I used to use STP and the clutch felt great for several years. Then the store went out of business and I switched to Wearever. I needed a new slave cyl. in a few days. Coincidence? Now I just run the GM stuff.

 

The clutch hydraulics has a flaw in it... Allowing dust to get into the fluid..
rather than spending the time to explain why... here is the deal....
You can suck all the fluid out of the master cylinder all you want, and you can spend the time to pump the clutch a million times, but you wont get it as clean... here is what you do. get two quarts of your favorite brand of clutch fluid...
get a turkey baster and a piece of 1/8th vacuum hose ( about 6 to 8 inches long )
You have to modify the end of the turkey baster tip to accept the 1/8th hose, making it air tight... you need one or two steps of hose to step down the tip to the size of the 1/8th hose...

To the process: ( this is an easy process without pumping the clutch pedal at all )
Suck out the fluid in the master cylinder ( this is best performed with an unmodified turkey baster... buy two turkey basters )
WARNING... be careful not to get any fluid on your paint. ( Try to make the master cylinder look like a surgical procedure, with lots of cloths and only the opening of the cylinder ,exposed... make sure the fender is covered completely...

Remove all the fluid from the master cylinder ( The CLUTCH MASTER )... then with a lint free cloth, wipe out the black residue at the bottom of the reservoir ( Note the small hole at the bottom of the reservoir ) Once this is clean ...fill the reservoir 1/2 way....
Now we are getting into the real trick... take the modified turkey baster, squeeze the ball and suck up some clean fluid from the container...any air bubbles in the baster will go to the top ( close to the Ball )... now put the 1/8 hose down into that hole at the bottom of the reservoir, and slowly inject ( squeeze the ball ) the clean fluid down inside that hole ( make sure the hose goes into the hole about 4 inches ) this is where all the caked up contaminants are clogging the system... Inject the clean fluid and it will flush ( wash out ) all this caked up clutch dust ) you will see all this black coming out of that hole at the bottom of the reservoir.. it will turn the clean fluid in the reservoir all black... ( Note when you squeeze the turkey bulb don't fear getting air into the system because any air bubble will float out and to the top of the fluid level in the reservoir )..
After two injections from the turkey baster ( fill it a couple of times) and inject.. NOW suck out all of this contaminated fluid from the reservoir.. using the initial method, including wiping out the inside with a lint free cloth..
Once this is done... refill 1/2 way again...insert the 1/8th hose from your injection baster.. and flush out the system again.. you will note that the amount of black contaminate will be much less.

Redue this procedure three times and refill to the top making sure the reservoir is clean. ( Also.. make sure the rubber diafram in the cap it clean)
Do this procedure once a year and you will not have any problems with your clutch hydraulics

If you have any problems with this procedure.. PM me.

Bill aka ET