MA6 clutch problem

[Jack O.]

I decided to put the MA6 dual disk clutch back in my car and apparently should have been a bit more attentive during the installation having never installed one before. The clutch does not disengage at all. When I run the motor, I cannot shift the trans. I didn't separate the one disk from the pressure plate and the other disk I installed the only way I thought it could go back in. I used the same length throwout bearing. I've adjusted the clutch to the point of removing all free play and can see that the clutch fork is indeed engaging as one would expect. Only thing that comes to mind is I put the one loose disk in backwards. This would be the disk that engages between the flywheel and pressure plate. The center of the disk projects out on one side and is level on the other. I installed the disk such that the side with the projecting center faces the pressure plate. I thought that was the only way it would install but I didn't try installing it such that the projection faced the flywheel. Anyone familiar with installation of these dual disk clucthes have any advice to offer? I don't know what else could be causing my problem. The tranny shifts fine when the engine isn't running and I haven't changed anything other than replacing the throwout bearing and switching out the aftermarket scatter shield for the original bellhousing.

Thanks in advance.

[Jim T.]

Re: MA6 clutch problem

Jack I guess there is not that much expertise on the dual disc 69 Corvette clutch viewing the posts here. I haven't put a clutch in my 68 since 73, so I had to view what is in the GM Corvette parts book illustrations. It appears that you installed the foward disc correctly with the raised center portion facing the pressure plate. I checked the parts book to see if there was a special throwout bearing for the dual disc 69. The parts book shows only one throwout bearing part number for 64-80 Corvettes. Just now in rereading what you posted, you wrote that you did not separate one disc from the pressure plate. Jack if the clutch disc is stuck to the pressure plate it will not disenguage and allow you to shift. The pressure place is retracting when you push in on the clutch and pulling the pressure plate back on the transmission splines and its turning the transmission shaft. If in fact this is your problem you do not have to disassemble the clutch to break it loose and some will say you should. It depends on the severity of the problem. Sometimes a disc can be broken loose by putting the car in gear and depressing the clutch, then using the starter, bump the engine over. Just remember the car is in gear and is going to move into a wall or another car or whatever is in front or in the rear of the car. Pull the coil wire to keep it from starting.

[Jack O.]

Re: MA6 clutch problem

Jim,
Thanks for the response. Unfortunately I don't have a good illustration of the clutch or a good understanding of how the 2nd disk (the one within the pressure plate) works. What you suggest sounds very feasible. The clutch was in the car and working fine just weeks before but I suppose something could have gotten bound up when I installed the trans - it was very difficult and I basically had to slowly "drive" it in using the trans bolts themselves. This may have effected the clutch in some way to cause it not to release. Best thing I have to go on now so I'll try your "starter" technique. What GM Corvette Parts book are you referring to?
Thanks again.

[Terry M.]

Re: MA6 clutch problem *TL*

Jack,
I have never had the opportunity to work on a dual disk clutch, but in my limited experience using the trans bolts or bellhousing bolts to "drive" the trans into place is never a good idea. Many mounting ears have been broken on the trans case using this technique.
You may try Jim's starter trick, but I believe in the final analysis you will have to take it back apart to see what has been forced together. It could be the pilot bearing or burrs on the input shaft splines.

[Jim T.]

Re: MA6 clutch problem

Jack I did not know that your clutch was working fine before you changed out the bell housings. In my opinion this rules out that the rear clutch disc is stuck to the pressure plate. In my experience this only happens when the car is not driven for months and is not garaged.You stating that you had to draw the transmission to the bell housing with the transmission bolts changes things. You could very well have something else wrong. I think you should loosen the bolts to the transmission and see if it backs out from the pressure of being pulled to the bellhousing. If it does not move, then it back an inch or less and see if you can push it back up to the bellhousing freely to verify it is okay. I don't think you would have to remove your shifter or driveshaft to do this, just the bolts through the rubber mount to the rear of the transmission.