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My clutch suddenly, without warning refuses to disengage. The clutch slave moves the arm but no disengagement. I tried adjusting the slave out for more travel and that worked perfectly last night but it stopped working when I tried it again today. The transmission shifts into gear smoothly with the engine off. There were no strange noises or problems prior to this problem. I'm thinking maybe throwout bearing but again no noise at all. All other throw out bearings that I've experienced made noises. I tried bleeding the system, no air observed.

Any help will be greatly appreciated.
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quote:
Originally posted by MARLIN JACK:
Dennis, Sounds like the 'Fingers' on the Pressure Plate may have worn through and/or Bent. It has happened on rare occasion. The problem Could NOT be the Clutch Master leaking, as the Slave Cylinder seems to be functioning properly. Marlin.
OK, let me run this past you guys and see what you think. I had my wife step on the clutch and through the "peep hole" I could see that the pressure plate was disengaging. The other night when I discovered that the clutch was not disengaging, I adjusted the slave further out and it worked fine until the next day when it again refused to disengage. Could it be that the clutch master/slave is not holding the line pressure and is not able to move the fork far enough? I have already bled the system and there was no air bubbles or leaks.

Thanks guys. I'm trying to figure out what I need to buy, the wife has me on car allowance that restricts me from buying experimental parts that don't need to be replaced. Frowner
Sounds like a situation of a slow leak somewhere in the master cylinder, hose or the salve itself.

I had a simular problem in where the system would hold it's pressure for about 2 or 3 days and then I would have no clutch. Bleed it again and everything would be fine for 2 or 3 days again. I did everything from adjusting the forks to adjusting the salve over and over again. But every couple of days, the same thing would happen.

I replaced my master and the salve and that solved my problem. Both the master and the salve on mine at the time were the original one's and not the upgraded new one's. Look under your dash in the peddle area, do you see any leakage around the clutch pedel firewall area ? How about the front trunk area where the clutch master is ?

Check all the fittings on the hoses and the hose itself, front to rear underneith the car, are they tight or showing any signs of a build up of grime or leaking anywhere along the lines ?

That's what it sounds like, a slow leak somewhere that's taking in air.

You might even want to try to undo all the fittings on the hoses, front to rear, put some plummers tape on the them and put them back on just to see if this helps hold the pressure for a longer period of time.
Last edited by coz
I've seen no leaks, air in the system, and have not noticed a drop in fluid level but a bad clutch master seems to be a viable problem. I'll take a look under the dash and pull the master to check for leakage. I notice that there are two bolts holding it onto the firewall, is there something else that needs to be removed to detach the clutch master from the pedal? Thanks for the assistance.
Dennis,
Chances are if you don't have any clutch peddle, you have air in the system. It takes a build up of pressure to disengage the clutch. I didn't find anything leaking either when mine was acting up. There's a good chance that everytime you push the peddle in, when you let it out is what's drawing air into the system.

Yes, there is a pin on the clutch peddle lever at the firewall attached to the push rod that works the piston inside the master that has to be disengaged before the master can be completely removed. It's a pain in the butt to get to under the dash and it helps to have small hands, but it can be done, just take your time and watch out for sharp edges. Remove the carter pin and disengage the peddle from the from the piston push rod. Then remove the master from the front trunk with the 2 bolts. Also the clutch line from the master. There is also a clip under the boot that has to be removed once out to remove the inside piston and spring. Note which way the piston comes out of the cylinder when your removing it so you know front from rear on the piston itself.

You may want to get a rebuilt kit before hand as long as your taking it off and rebuild the insides with new O rings and seals on the cylinder piston and housing. Be sure to look inside the cylinder for any kind of pitting. If it's pitted, you'll have to hone it out. But this is very tricky, to much or if it's too pitted it will not seal. The cylinders also tend to get out of round from pitting and wear in which case nothing you do will seal it again. Been there and done that too. I ended up buying a new one from Jerry at PI for 100.00 and replaced the whole thing because mine was just too pitted after trying to reseal it the first time. Nothing like doing it twice....

Mike Daily's got some great info on it on his site that helped me get through it....(Thanks Mike !)
http://www.panteraplace.com/page153.htm

Oh, one more thing. If you change out the entire master, your going to have to probably cut your clutch line right at the conncetion fitting and buy a new fitting and reflare the end of the line. Be real careful you don't cut it to short otherwise you won't have enough clutch line to reconnect to the master. Been there and did that too. :-) I ended up putting an extension on my line to reach.
Good luck, let me know how it's coming.
Last edited by coz
This just happened to me.... I had the trans out and preped and WATER sanded the inner rear fenders.. I got the clutch wet and it rusted to the flywheel and pressure plate in a matter of days. I put it back together to realize it would not realease.. I started it in gear and jerked it around a bit, when it broke loose, it disinigrated the disc. I replaced the flywheel and used a 10.5 inch Centerforce from Hall. $665 later it works fine now. It is not that bad a job. I used a 17 inch 1x4 under the back of the oil pan to hold the rear of the engine up.Just between the engine and trans. Highly recommend all new internal clutch stuff. Keep it dry!
OK, next chapter. I took the hydraulic clutch system all apart and cleaned all parts. Filled with new fluid and bled the system. Same results. I checked the clearance at the pressure plate and although it moves, it is not the .030 that Jack DeRyke says it should be. I couldn't get the gage in between. I tried adjusting the slave out but the clearance stays the same no matter how much I move it. I'm kind of thinking that the master/slave is pushing to a certain pressure limit then stalling there. I've checked for leaks and found none and also bled the system several times . . .no air. Any thoughts or recommendations? Thanks for all the help guys.
When you say you took everything a part and cleaned it, are you saying you took the master and the salve a part and cleaned them ?
What kind of shape were the O rings in ? Are they flat or still have roundness to them ? Any pitting in the cylinder of the master ?
You could still not be building the pressure it needs. When your bleeding the system, how much pressure is there expelling the fluid from the slave valve ? It should be pretty forceful.
I cleaned out the master, flushed all out. It was changed in may of 2003 and is I believe a aluminum Hall Pantera unit w/stainless bore. I believe that the slave unit is original. The internal rubber all looked good. I purged and replaced all the fluid and gave it a good bleeding. It puts out great pressure at the slave. There was not enough gap (.030)at the pressure plate with the clutch depressed. I attempted to adjust the slave rod but no matter how much length I gave it the pressure plate gap didn't increase. There are no leaks nor loss of fluid. I'm beginning to think that the slave stops pushing at a certain line pressure which is why no clutch even with the adjusting rod turned out.

Thanks for the help.
Dennis,
There is one more thing you can try before taking the ZF & Clutch out, but I'm not sure how to explain it here in writing. Send me an e-mail with you phone number and I'll call you to explain it while you looking at the slave area.
cozland@cox.net.
Basically, you might want to advance the disengagement lever arm thats coming out of the ZF on the passenger side below the salve one notch towards the front end of the car. This will give you more push for the disengagement when you can't get enough from the salve adjustment push rod. I had to do this to mine too. Then you can re-adjust the salve push rod for the gap your looking for.
When I talk to you, I'll be able to explain it better to you.
Last edited by coz
I think I know what you are talking about, Jack DeRyke suggested it too. Loosen the pinch bolt that holds the bell crank on the shaft. Remove the shaft and advance it towards the front of the car to allow you more leverage and turn the slave rod back in to adjust for the added leverage at the crank. Is that what you were referring to? I was planning to tackle that tomorrow. Thanks
Moving the bell crank forward to provide more throw didn't work. At one point the pedal pressure seemed harder and the gap was even less. I'm going to shelf this one until I go to Vegas in April and pick up a new slave unit. Hopefully this will solve the problem. Well, the cheapest and least labor intensive solutions first! Thanks to all who offered help, you guys are the best! See you in Vegas!
I recently had my ZF rebuilt and installed a new centerforce style clutch while it was all apart. When I got it back together the clutch didn't always fully disengage and the release point on the clutch pedal was way down towords the floor.
I got a "long throw" slave cylinder from Pantera Performance and it cleared up both problems. Now the clutch disengages correctly and the pedal releases nearer the middle of the travel, making shifting and waiting at stoplights in gear, more comfortable.
The point is, even if it doesn't clear up your problem, the long throw slave makes the clutch pedal behave more "normally" and might be worth the investment, just for that. It sure made it easier for my wife to drive it...and that's a good thing...the way I've been spending money on it lately!
Good luck, Mooso.
If you end up having to remove your ZF, here's something to keep in mind. Check to see if you have a stock oil pan or, if you're really lucky, a nice stiff aftermarket pan or aluminum pan.
You have to "tilt" the engine and trans to get it out of the car. The rear of the trans has to be raised up to pull the whole thing back far enough to get the center shaft to clear the clutch. To do this, you have to put a block of wood under the oil pan at the farthest back poistion you can and jack it up a bit. The stock pan is very likely to compress upward into the crank. Mine did. Many others have too.
There are a couple of ways to go about fixing this if it happens. Pantera Performance makes removable, bolt in, crossmember and parking brake brackets. You sawsall the old ones out and drill and bolt the new ones in. This allows you to remove and replace the pan with a heavy duty one.
I, however, chose the hillbilly method. When I fired up the motor and the crank was "clacking" off the pan, I shut it down. Called a towing service with a flatbed. $50 later I was at my friend's welding shop. We pushed the car over the pit. Got a slide hammer. Tack welded a large nut to a large washer. Tack welded that assembly to the bottom of the steel oil pan. Screwed in the slide hammer. Gave it a couple of pulls. Problem solved. No one can see this mickey mouse stuff, so don't tell anyone I did it.
I brought along oil and a filter and when we had confirmed the crank was no longer hitting, I changed the oil and drove home.
I know that this approach will crystalize some oil at the tack welds and I know that this approach is going to horrify some folks, but we kept the tack welds small and the heat low. It didn't require much force to pop the pan out.
If I ever pull the motor for a rebuild you can bet I will buy the crossmembers and a HD oil pan. But for now...hillbilly ho!
Later, Mooso.
The clutch mystery is solved. A friend dropped by with his pal who just happens to be a whiz kid with the Japanese import race cars here. He took a look at the car and fixed it in a few minutes. He related that hydraulic clutches have air bubbles that stick in the lines. As I pumped the fluid through the lines, he tapped on the lines and sure enough bubbles that hadn't come out during normal bleeding exited the bleed screw (I guess that the tapping on the lines released the bubbles). Prior to this, I had pumped a large bottle of hydraulic fluid through the lines in attempt to clear the bubbles, completely replacing all fluid without getting all of the air out. During this time, the line ejected bubbles and eventually came out clear. I guess that he was right, more bubbles eventually came out and the clutch now works.

Thanks to all that offered help!
Last edited by 4nford
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