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C4 Clutch adjustment

18K views 9 replies 9 participants last post by  86 vett vert 
#1 ·
I bought a 1985 with manual trans that seems totally original, very well kept with 120,000 miles. I have to pump the clutch pedal to get in/out of gear. My mechanic replaced the master and slave cylinders and hose and that didn't help. Next was the disc, pressure plate and bearing but still no difference. The system has been bled with a vacuum while the slave was turned 45 degrees and STILL nothing. My car has been in the shop for 3 months and he's out of ideas. Any suggestions?
 
#2 ·
There was a lot of discussion on another forum about this last year. Seems that all of the new slave cylinders were assembled incorrectly and never worked right. Not sure if that is what you are experiencing, but having to pump up pressure does sound like it is either a bad slave or master cylinder.
 
#4 ·
How are they bleeding the system? Using the pedal or a brake flushing machine? Try holding the pedal down flat, & gravity bleeding it. You might have to unbolt the clutch master, use a brake flushing mach. hold the master cyl. at a slight angle, the line (that goes down to the slave) needs to be higher, so the whole master fills up.
I hope that helps you. I was working on a mid 90s ranger that had a bleeding problem, the master was at a 45 degree angle when bolted to the fire wall. The effect is like turning a cup upside down & putting it into water, there will be a hugh air pocket.
 
#5 ·
Just cause the master cyl is new doesn't mean it's good. I put a new master cyl on my 87 and it was no good. Drives you nuts when new parts are no good and you think they are. I would try another master. Take the new one apart and see if the rubber cup at the end plunger is cut. I bet it is. Later B.A.:cheers:
 
#6 ·
. My car has been in the shop for 3 months and he's out of ideas. Any suggestions?

Take it to a different shop.
Seriously.

I replaced my master cylinder a few years ago.
To bleed the system completely of all air, here is what I did after suffering thru the same symptoms you have.


Jacked up the front end, went under the car and removed the slave cylinder from bell holusing.

Removed cap from master cylinder and put a towel around the cup. Back under the car, I took a long, large philips screwdriver and pushed the slave piston all the way in. This caused the master to purge much fluid out of the cup. Released the slave, filled the cup, and repeated pushing the slave piston in. Did this 3 times.

Next, Filled the cup and put the cap back on master, re-assembled slave to bell housing and hooked clutch back up, had the wife jump in the car. Had her pump the clutch 20 or more times andf on the last pump/push, hold the pedal down. Bled of the slave, closed the bleeder, had wife release clutch pedal.

Clutch works as if it just came off factory floor.

15 minutes/ done.
 
#10 ·
:duel: another thing as far fetched as it may sound is try a little bead of weld on the end of the fork on clutch peddle it gives you just a little more adjustment on the clutch :thumbsup: it worked for me when i rebuilt the trans,and put a new clutch pressure plate and throwout bearing in last year :seeya:let me know how you make out the fork does ware out and was a easy fix once i figured out to give it a try ,it worked and have not had any problems since:burnout:
 
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