1969 clutch will not disengage

[Donald H.]

I'm helping a friend work on his 69 350/350. We are both very 'shade tree' when it comes to the mechanics but we both enjoy doing our own work. We have installed a new flywheel new clutch/pressure plate set (diaphragm type bought from Paragon and the one the Paragon techs say they use), new Zbar/bellcrank, new clutch fork, fork to bellcrank rod and all the related small parts.

We can not get the clutch to disengage. We have adjusted the pedal to bellcrank rod all the way out and still not enough. Before we tear it apart again, following are some of what we did before hand:

We compared the new bellcrank to the old one and they seem to be the same.
We compared the clutch fork to the new one and they are the same.

I searched the forum and could not find anything, but I seem to recall that there is a short and a long throwout bearing. We didn't compare the old versus new that closely. But what I recall is the shorter throwout bearing is correct for the Corvette. If that is the case, does anyone know what the measurement would be from the faces of the clutch fork to the face of the throughout bearing?

My friend bough a new clutch fork ball (1 1/2"), but was told by the techs at Paragon that if he had the 1 3/8") ball he should re-use it unless it was completely shot. His car did have the 1 3/8" and we did re-use it. Would using the 1 1/2" fork ball make much, or enough difference to get the throwout bearing closer to the pressure plate fingers?

Thank,

Don

[Joe L.]

Re: 1969 clutch will not disengage

I'm helping a friend work on his 69 350/350. We are both very 'shade tree' when it comes to the mechanics but we both enjoy doing our own work. We have installed a new flywheel new clutch/pressure plate set (diaphragm type bought from Paragon and the one the Paragon techs say they use), new Zbar/bellcrank, new clutch fork, fork to bellcrank rod and all the related small parts.

We can not get the clutch to disengage. We have adjusted the pedal to bellcrank rod all the way out and still not enough. Before we tear it apart again, following are some of what we did before hand:

We compared the new bellcrank to the old one and they seem to be the same.
We compared the clutch fork to the new one and they are the same.

I searched the forum and could not find anything, but I seem to recall that there is a short and a long throwout bearing. We didn't compare the old versus new that closely. But what I recall is the shorter throwout bearing is correct for the Corvette. If that is the case, does anyone know what the measurement would be from the faces of the clutch fork to the face of the throughout bearing?

My friend bough a new clutch fork ball (1 1/2"), but was told by the techs at Paragon that if he had the 1 3/8") ball he should re-use it unless it was completely shot. His car did have the 1 3/8" and we did re-use it. Would using the 1 1/2" fork ball make much, or enough difference to get the throwout bearing closer to the pressure plate fingers?

Thank,

Don

Don------


The original clutch fork ball stud for 1969 applications was 1-3/8" overall length. However, the 1-1/2" will work perfectly. In fact, all L1975-81 Corvettes originally used the 1-1/2" ball stud and those cars have EXACTLY the same clutch system as 1968-E75. My guess is that GM found the 1-1/2" stud to be better than the 1-3/8" and that's why they went back to it (1955-65 also used the 1-1/2" stud).

All Corvettes (except early 1955) MUST use the short clutch release bearing. This bearing is 1-1/4" in length (face to rear-most part of bearing). The common "long" bearing is 1-7/8" and MUST NOT be used on a Corvette.

I don't know or know of any way of measuring the dimension that you seem to be asking for regarding the face of clutch fork to release bearing measurement.

[Michael B.]

Re: 1969 clutch will not disengage

I replaced my stock clutch with a CenterForce Dual Friction and it required nearly all the adjustment to get it to release, still lower than I expected but it does release. One possibility with the correct parts is that the friction disk is in backwards. Springs go towards the transmission. If it's backwards the springs will contact the flywheel bolts and not release.