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Clutch concerns!



The clutch pedal seems to need more and more pressure to release. The clutch engages and releases, but it feels like I am grinding somting.:eek

Has anyone else had this condition?
Is there a way to lube or check the fork ball while still in the car??

Good Luck

Hey Rick good seeing ya here.
Hope someone can come up with some help for ya.

L98 DN4+3


There is no lubrication for any part of the clutch linkage. It is completely hydralic, (master and slave cylinder). You must take it apart and replace the clutch components. I recommend an entire clutch pack, (pressure plate, disk, throwout bearing and alignment tool). While you have it out check the flywheel it may need to be resurfaced. Check the collar (bearing retainer) on the front of the transmission. Mine was cracked by a previous clutch install and broke off completely when we pulled the trans. At the same time replace the pilot bushing, (center of flywheel). If you have the flywheel resurfaced it must be shimed upon replacement. The reason for shimming the flywheel is because the hydralic clutch has no adjustment, (it's self-adjusting). Ask me how I know, I found out the hard way. Also while you're at it you might as well change filter and fluid in DN overdrive unit. That's suspossed to be serviced every 10,000 miles.

Pulling tranny seems drastic...

But whats a guy to do?? I may ask Bud to drive it and give me his opinion...


Good Luck this weekend...

Hey Rick,
Hope our discussion proves fruitful for you this weekend. I think you maybe on the right track with the heat being a problem. As we discussed by the clutch cylinder making contact with the exhaust cat on that side means there is direct heat transfer.. Good Luck trying to insulate it a little.. Keep us posted ;) by the way where did the cat back system come from that you installed? GM?

I think I found it

Last night on my way home from work, the clutch pedal stuck engaged, then suddenly released. (no damage).

I got the car home and removed the under dash cover, and inspected the pedals. I found oil leaking from the master cylander boot, and the bushing was missing. I guess this is a good time to break down and change out the master cylander.

I will let you all know how it turns out later.

Master Cylinder


It sounds like it's time to change the master cylinder. When you do I recommend that you also change the slave cylinder. BTW, if you haven't priced them hold on to your seat. It blew me away.
Fixed it!!

Went to dealer and bought new master cylander...$200. Ouch!!! :(

While at dealer I discovered this issue:

All C4's pre-1988 requier new brake pedal to recieve all new master cylanders. Ykes!! :eek
The reason was the new cylander rod busing diameter is .375", and the old ones are .41".

I went under the dash and attempted to measure the pin on mine to verify the dimension. ( I was going to drill the new cylander bushing to the .41" instead of replacing the pedal). While attempting I noticed the plastic bushing/keeper in the cylander bore looked smashed, and the alighnment of the rod was way off. I re-alligned the rod on the pin and tried the pedal. The clutch felt good for two pumps and felt bad again. I checked the alignment again and it was back to the bad position. I removed the bushing from the push rod and found the keeper fingers were broken.

For a simple repair do the following:

1. Remove the bushing from the cylander rod.
2. Cut off the keeper fingers.
3. Reinstall the bushing.
4. Apply grease to pedal pin, reinstall cylander rod.
5. Install a 1/4" diameter hairpin clip in the depression on the peadal pin.


Total cost to me was .19. The hairpin clips are available at fine hardware stores everywhere!

By looking at the bad design of the keeper/bushing setup, I would recommend all pre 88 C4's check for this problem, and replace the bushing keeper with a pin clip.

Will be returning the master cylander today and getting some new shocks instead!!!
Tip on Bleeding the slave

If you have low pedal pressure ( have to mash it to the floor to get it to disengage) assuming all linkage issues are ok!
Remove the slave from the housing get the bleeder valve facing up and bleed away. You can't get all the air out if you bleed it on the car, the piston faces slightly up trapping nasty bubbles.Ive also seen people make their own extended length pushrods to workaround this problem.

My .02


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