Finally decided to put a new clutch assembly in my /6 conversion.

After bolting everything back up and test driving the car, I have horrible clutch chatter/judder starting off in first. Old clutch slipped when foot to the floor in 3rd gear.

Old clutch cover and flywheel surface did not have any blueish burn marks on it.

Problem: the two bottom mounting studs for the tranny to engine appear to be pulling out (won't tighten), so before I pull the assembly again and try to helicoil the pulled threads, the question is .. ta da..:

Would this cause severe clutch chatter/judder in 1st gear? Asking for opinions/experience as I have never experienced this condition in any of my cars.

I do have a spare flywheel and just need to find a machinist competent enough to surface it and hold the correct dimensions, but if that's not the problem it would be a waste of money.

If those two studs are not tightening at all do this.
Get the car up on jack stands. (!)
Get under the car with a good light. Engine off.
Have an assistant push the clutch pedal to the floor as you watch the engine/trans joint.
If they push apart, that is your chatter.

double

Cool and thanks ... That I will do.

The conclusion .... The two bottom transmission studs pulled out. One is on a highway somewhere. Two days of work pulling everything apart and heli-coiling the two bottom studs the clutch now engages like butter.

I had jacked up the car and had a friend push in on the clutch. I could not see any movement. By the time I got it on a lift to inspect the assembly, the trans had separated from the engine about 1/2" at the bottom (I could see the clutch assembly easily) ... enough that the ring gear had machined the interior of the trans bell housing slightly. Sorry, no pictures.

I now know to inspect the studs on a 40+ year old magnesium case. The two upper studs were not enough to hold the drive train together and fortunately they did not pull, but were loose.

Now to put some miles on it to see if the repair I did will hold. I will eventually pull the drive train and use Time-Serts on the two lower studs .... maybe Time-Sert all of the stud holes.

Lesson learned.

Yes.