[llong66]

Well, I finally found my clutch issue that I have had since I bought the car, its fluid leaking out the back of the master cyl, the part inside the car. Anyway, I got a new one and got it on but I cannot get it blead, or atleast I think thats the issue. When I start the car and try to run through the gears I cant, it grinds trying to get into gear.
I have tried just pumpimg and pumping it, basically trying to gravity bleed it, no luck. I have tried the one man bleeder, the lil $40 deal you get at advanced auto, no luck. I have a friend comming over tomorrow and am going to try the oldfashioned pump hold, bleed,pump, hold, bleed method as well as FSM manual procedure. I have changed the slave cyl a cpl of times and had no real trouble getting it blead. Is this normal? Does anyone hav a bleeding trick for the clutch? Thanks alot!

 

[BonneRisque]

The master should have already come pre blead

But I would have pre blead it anyway

You may have to keep working it, and Mighty Vac it till all the air bubbles have been removed from the system

 

[blkvette94]

best method I've found is the old school way+. Take the slave cylinder off the car and let it hang held by wire at almost a straight up and down angle-- so the bleeder is pointing straight up. pump the pedal very, very slowly until the slave cylinder bottoms out on the c ring inside. yes this will have the cylinder over filled.

Tap the slave, the line and the master to move the bubbles and wait a minute or so--with someone pushing in on the pedal crack the valve and let the air out.

at this point go old school on the bleeding for several pumps...

at this time the slave is full and there shouldn't be any air-- the pedal will be hard or impossible to push at the very top

here's the tricky-messy part. using a screwdriver or the push rod to push in the slave cylinder barely crack the bleeder and push the slave in until it bottoms out.

reinstall the slave-- pump the pedal until you see clutch movement, then give it one or two more old school bleeds.

The keys I found are the very very slow pumping and bleeding the slave with it off so the buble go to the highest point.

Also for those with a non ZF trans--if you don't have the ruber cover anymore the clutch fork cover and pedal push rod boot for a 79 work. Corvette centrals numbers are 533745 and 532752. Cut the end off the pedal pushrod cover and it fits over the slave end. to make the fork cover work cut the back side of fork cover off just at the bottom where the groves are for it to fit into the bell housing

 

[llong66]

Well my buddy came by and we did the factory service manual method as well as the method in blkvette94s post and no luck. I had let the slave cyl hang all night with the bleed screw in the up position too. I know I am getting fluid to circulate because I can see some color in the fluid in the master cylinder now from the old fluid left in the slave cylinder/line.
I removed the slave cyl from the bell housing and pumped the clutch/added fluid until the only movement in the pedal I had was from the play in the linkage. From that point I did the oldfashoned bleed method, no luck.
What happens is I can pull the car in and out of the fwd gears but when in gear it rattles, jumps, sometimes grinds in and outa gear, if I let off the brakes it wants to lunge fwd even with the clutch depressed. I cannot get it in rev at all while running. My buddy thinks there is another problem and that the clutch is engaging. I disagree, the clutch feels like its not engaging fully. The entire clutch/flywheel, TO bearing, etc were replaced less than 5000 miles ago so I dont feel its those parts. Any other ideas where I might look??

 

[BonneRisque]

Your going to have to pressure Bleed the entire system

http://store.motiveproducts.com/storefront.aspx

 

[llong66]

BonneRisque, whats the deal woth the product you listed, have you used it and how does it work? I cannot find a usersmanual for it.
Is it not unusual to have problem bleeding this system? Its so simple it should bleed right out but its not.

 

[blkvette94]

Well my buddy came by and we did the factory service manual method as well as the method in blkvette94s post and no luck. I had let the slave cyl hang all night with the bleed screw in the up position too. I know I am getting fluid to circulate because I can see some color in the fluid in the master cylinder now from the old fluid left in the slave cylinder/line.
I removed the slave cyl from the bell housing and pumped the clutch/added fluid until the only movement in the pedal I had was from the play in the linkage. From that point I did the oldfashoned bleed method, no luck.
What happens is I can pull the car in and out of the fwd gears but when in gear it rattles, jumps, sometimes grinds in and outa gear, if I let off the brakes it wants to lunge fwd even with the clutch depressed. I cannot get it in rev at all while running. My buddy thinks there is another problem and that the clutch is engaging. I disagree, the clutch feels like its not engaging fully. The entire clutch/flywheel, TO bearing, etc were replaced less than 5000 miles ago so I dont feel its those parts. Any other ideas where I might look??

Are you noticing any bulging of the line where the rubber parts are?
did this start soon after the replacement of the clutch? Can you tell if the TO bearing is installed correctly?

Did the trans go back on smoothly?

did you replace the slave cylinder recently? maybe it's time?

 

[llong66]

Are you noticing any bulging of the line where the rubber parts are?
did this start soon after the replacement of the clutch? Can you tell if the TO bearing is installed correctly?

Did the trans go back on smoothly?

did you replace the slave cylinder recently? maybe it's time?

There is no buldging of the line that I can see anyplace. The car has about 5k on it after the clutch replacement.
I talked to my local shop and vette guru today and he said he has done plenty of these and never needed a power bleeder. He does what I did, let gravity work for the most part and a lil pumping/old school bleeding after that.
He felt maybe the thing to do was try replacing the slave cyl.
It boils down to the fact that I am not getting enough travel in the slave cyl. Its just a matter of whats failing, I mean they system is only 3 parts! I am not sure what to do next

 

[blkvette94]

There is no buldging of the line that I can see anyplace. The car has about 5k on it after the clutch replacement.
I talked to my local shop and vette guru today and he said he has done plenty of these and never needed a power bleeder. He does what I did, let gravity work for the most part and a lil pumping/old school bleeding after that.
He felt maybe the thing to do was try replacing the slave cyl.
It boils down to the fact that I am not getting enough travel in the slave cyl. Its just a matter of whats failing, I mean they system is only 3 parts! I am not sure what to do next

Not sure how well you can check the fork for damage/wear over time. one other thing I've done is made a new pusher rod. I'm not sure if that's integral to your slave or not.. It's not on my 86. Simply bought a grade 8 bolt cut off the head and ground it to resemble the current pusher--plus about half an inch. It caused my slave to be almost bottomed out. and helped quite a bit also. I feel your pain though. mine was hitting the floor before it disengaged

 

[BonneRisque]

BonneRisque, whats the deal woth the product you listed, have you used it and how does it work? I cannot find a usersmanual for it.
Is it not unusual to have problem bleeding this system? Its so simple it should bleed right out but its not.

pro mechanics use them all the time

They work

Also in the past I work on the lines After I have heated up the fluid within them

It dissipates the air in the lines much better and further thins the fluid within them

 

[jim6802]

I fought this a little last year. I had to change the line. Rubber was coming apart. Had to replace it with a steel braded line, couldnt find an original but didnt try real hard either. Had trouble bleeding used fsm procedure and it worked. If you want to check clutch release, put car on jackstands and in gear. Have someone push clutch pedal while you are trying to turn drive shaft by hand. If you can turn it in gear with pedal down you have release. As you are turning drive shaft by hand have helper let off pedal and you should be able to feel when clutch grabs.

 

[crowvet]

As a automotive tech, I have been in this position a few times. I will share my "trick" arsenal with you. #1 The easiest.... Do you remember the old service station pump dispensers that fit on a one gallon can? You pull the handle up then pull on a release ball to dispense the fluid. I hook a vacuum hose to the end of this and then open the bleeder valve on the slave and back fill the system from the bottom. Works nearly every time. #2 Time consuming but also works, With a old clutch master cap, modify it with a nipple. Then hook a hand held vacuum pump to it and pump up about 30inches of vacuum. Let it sit and continue to do this when the vacuum bleeds off. This can take a couple days, but it will slowly pull the air out of the system. #3 most people pump to fast not allowing the fluid to re-enter the master cylinder chamber. Therefore they are continuously pumping fresh air into the system. SLOW down and allow time between pumps. It is also more effective at times to not pump, by this i mean.... Loosen the bleeder push the pedal down once.... tighten the bleeder and bring the pedal up. Loosen bleeder, pedal down, tighten bleeder, pedal up. NO Pumping.Hope this helps you:cheers:

 

[llong66]

thanks so much for all of your help. I have decided to replace the slave and start from there. At that point all thats left of the clutch system in the line between the two and I dont think thats it, it visually checks fine. I figure if it was the master cyl that was the problem, it would leak down when I let the slave piston extend all the way as described above and it does not. This leaves a defective slave...which is a reman and I have had trouble with them before or the line.
Oh well, the new slave is special order if I want the OEM and I do so its a wait, maybe I can get my radieator installed or my C5 brakes put on

 

[atgordon]

When I rebuilt my 94 LT1, I did replace the slave cylinder, and was concerned that it would prove difficult to bleed (the nipple pointing down doesn't help).

After much searching and using the FSM, two-person bleeding, pressure bleeding and cursing and drinking beer, and finding that nothing worked, I came across a couple of old timer Corvette forum postings that offered the following self bleeding technique:

Remove the master cylinder cap, remove rubber insert so it can be filled 75% full. Close bleed nipple on slave. Start pumping the pedal to the floor and release steadily. Do this 10 times and check the fluid level in MC (if it is down, then you still have a leak). If OK, continue pumping the pedal steadily: expect to do this for 200-300 times before sensing resistance. Keep pumping until you get full operation.

The hydraulic fluid will appear very creamy, just like Guinness, as a result of the air bled out through the MC.

As a teenager, I worked in a repair shop and bled my fair share of brakes and clutch systems, and thought this was never going to work ... but it did. I should add, I gave up counting, so it might have been over 300 pedal depressions, but I was so PO'd by the problems we'd had and the time we'd spent on bleeding the new SC, I was willing to get a rosary out if I thought it would help, and after a while, I began to detect the pedal coming in, and just kept on going until I had a full pedal.