Hello Everyone,

Trying to help my son with his 76 C3. He sent to mid america for a new clutch release fork, as half the clip that goes around the pivot stud was broken off. So when he had the car apart, he threw away the old release fork. (Not too good) Had to take it apart after he did the job, because the release bearing came out of the fork.

Any way, put in a new clutch kit with the pilot bushing, disk, pressure plate and cover, and another new release bearing. The back of the flywheel cleaned up very well. A new fork pivot stud was installed (which was a 1/4" longer than the one that was in there. Looked like it had been in there for a long time.)

Cleaned up everything, and reinstalled.

Problem, the adjustment lever on the pedal push rod from the clutch pedal is all the way out at the end of the rod, and still will not release the clutch disk. If the nut is adjusted back towards the firewall about 1/2" or so, the release bearing will loose contact with the fingers of the pressure plate.

I think Mid America might have sent him the wrong fork??????

Anyway, is there a way to get out of this mess? Can a longer fork push rod be put in, without messing up the geometry of all the other parts? The rod must be an origional length as it is about 9 3/16" end to end.

Or is there another part that we are overlooking, that might be the culprit?

Any help would be appreciated.

Ed

 

Every time the flywheel is cut, the adjustment moves further out on the adjustable push rod. I remedy this by cutting the lower push-rod and extending it about 1 inch using hollow 3/8 inch steel tubing. Welding is required.

 

The length of the pivot stud is important, sounds like the 1/4" extra length may be your problem.

 

First of all you want the pivot ball stud all the way in the bell housing. That sets the starting point of the throwout bearing.

Yes, you can get or make a longer cross shaft to clutch fork rods.

My orginal Keisler kit cross shaft setup required me to put my foot to the floor to disengage the clutch with the upper adjustment nut at the end. I drilled two additional holes in the upper arm closer to the center of rotation. This made less petal movement move the clutch arm more.

 

Thanks for the comments.

I wanted to make sure that someone had gone the longer rod route before. And it would work OK.

Have a good day

Ed

 

Could the problem be this?

If the fork is in the large grove of the throw out bearing, instead of the fork and clips around the small lip on the rear of the bearing, is this the trouble?



That would be the 1" of adjustment that is missing???

Ed

 

The fork and the spring clips belong inside the groove in the t/o bearing.

 

Correct me if I'm wrong, but if you want to disengage the clutch then you need to shorten the rod...i.e. move the adjusting nut toward the firewall.

The flywheel surfacing won't be much more than maybe 2/100 of an inch. But, the 1/4" (25/100 of an inch) longer pivot ball stud can be a problem...though you should have had plenty of room for adjustment.

There is an adjustable pivot ball stud available that will fix this problem...Centerforce sells one.

Another problem could be that you don't have the throw-out bearing properly clipped onto the fork...it should slide onto the fork with the edges of the bearing under the spring tanks, but the bearing body outside of the springs...I've seen someone (OK...it was me I was watching)...stick the entire bearing under the springs which resulted in the spring touching the pressure plate, but fortunately they (OK me) noticed the problem before installing the tranny.

 

IMO, I think the rods need to be longer...but I agree that the 1/4" off on the stud could make or break the effectiveness of the mechanism because that 1/4" is magnified at the throwout. If this stud is correct, the rods shouldn't have to be welded or anything...

 

Confusing,

Between talking to a shop and the message board, I have two ways of installing the T/O bearing on the fork.

One way is that the fork and the spring clips go inside the large groove of the T/O bearing. And the spring clips hold it in the groove.

The other way is that the spring clips on the fork, clip on to the small flange of the T/O bearing (the trannie side) and the fork fingers are only THING in side the large groove of the T/O bearing.

I wish there was a nice article or pictures available to show which way it really is.

Ed

 

"One way is that the fork and the spring clips go inside the large groove of the T/O bearing. And the spring clips hold it in the groove."

This is the only way you should assemble the fork into the bearing.

Next...if you lengthen the rod, you need to be sure the fork does not hit the firewall before the clutch disengages.

It seems to me that a ball stud 1/4" longer will be sufficient to take care of the effect of machining the flywheel. It is possible that the throwout bearing is too short....causing the outer end of the fork to be too far back. If that is the case, a longer t/o bearing or an even longer ball stud could fix it.

Just some more thought...

Joe

 

Repair Manuals really go a long way. The Haynes Manual has some very good photos...it also indicates that the L82 and L48 used different ball studs...perhaps you have the wrong one.

 

I think they also make a short and long throw out bearing. You would want the thicker one with your problem