MTFCA Forum

Back in November, just before I left my beloved Barn, my coupe died just as I arrived home from a tour into the upper desert.

Initially we thought it was somewhere in the rear axle as through the transmission inspection hole we could see the brake drum rotating. As I was planning a move from Ramkna to La Mesa, I dragged the Coupe to a friends garage and we pulled the rear axle. Considering it hasn’t been touched for over thirty years, it was perfect.

So our attention returned to the transmission where we saw a potential problem. Once the fourth main was removed, the shaft which connects to the UJ was loose. Reluctantly I pushed the problem to one side while I completed the move to my new home.

On Sunday I started to remove the motor and completed the work this morning. Sure enough the eight rivets holding the output shaft to the clutch backing plate have all pulled out.
I have never seen this problem previously, anyone else seen anything like it?

I use a Watts clutch and the recommended stronger spring. Could it have caused the failure?

That Sucks Tony. Was it a re-riveted plate?

Hank

I bought the coupe in 1976 and as far as I know it has never been tampered with over the years.

I have found a few with loose rivets, but never one that has failed like that. If there is no damage, it could just be riveted back together. I would suggest that the driven plate be further countersunk so more of the rivet is left to hold the plate in place. It may be that that plate was machined after a previous re-riveting to clean up the face/rivet ends, and a little too much material was removed.

Hope this helps.
Allan from down under.

I have a couple of re riveted plates in my parts bucket. They seem to be tight but I use one that seems to look original when I do a rebuild. In my opinion I wouldn’t use that one again since it ran loose for a while and could have wallowed out the holes just a little.
The plates are pretty common and I would use another one.
But that’s my opinion. It can be repaired and probably be OK.

I have heard of that a couple times before. Unusual, but it does happen. I know Ed Archer did that on number 4 about twenty to thirty years ago.
I also have had a couple driven plates with loose rivets. I always check them closely when I put an engine together.

I have seen loose rivets, but never any that pulled all the way out. In fact the day before the 1996 SCVMTFC endurance run #36 had loose rivets, well no time to pull the engine then, so stuck a mig welder in there and welded the loose ones. that temporary fixed it enough with a clutch finger adjustment to complete the race the next day. Engine was pulled a few weeks later and new part put in.

Tim

I was going to say the same thing happened to me until I reread that your coupe died. I sheared those 8 rivets but the engine kept running. Just pressing down on the clutch pedal had no effect...major surgery time and commo with Big Flats Rivets was in order. I just considered it a failure due to soft Metal age.

Be sure to check the driven plate where the rivets set. They are bad to crack there. Check between the holes. There are more with cracks then without. Dan

Sorry that happened, however, you were fortunate it happened so close to home. It would have been a real problem if it had happened on a long tour. Hopefully you can get it back to running order soon and into it's new home.
Norm