VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Universal joint, closed driveline function?

I just replaced the clutch in my 1940 chevy, and now have a major leak/vibration coming from the u-joint/bell sleeve area.

I pulled the joint apart, and found a large amount of "end play" between the "spider" and the two "yokes". (nearly 3/16 inch). The bearings all seem nice and tight. There are no metal shavings or other indications of wear. I found a used replacement from an good running car (new replacements are not presently available); and it has the same play.

At this point, I am wondering if my problem is with the bell sleeve? If it is fixed rigidly to both the transmission and torque tube, the u joint should be centered and not wobble. Would still need to have the bell be free to rotate in the transmission case however.

Could it be that I just haven't tightend the sleeve sufficiently?

Has anyone else encountered this issue? and if so how have you resolved it.

The end play is normal. The U joint can center its self as the r torque tube moves up and down, etc. The bell helps to center the U joint with the torque tube. The threaded nut at the rear of the bell compresses a seal to prevent leakage at that point. The original seal was a rubberized felt and compressed easily. Today they give you a hard piece of cork and the nut has to be tightened and retightened several times to compress the cork.
The bell fits into the rear of the transmission extension. It should be tight enough to move up and down but not have any free play. Paper shims are used to adjust.

Along with Gene's info, there's also a Good bit of related info in the '42-'48 section.

If the ball housing (bell sleeve) is too tight it will not rotate easy enough in the transmission. That will cause the torque tube and U-joint to be off center resulting in vibration.

If the torque tube is bent that could cause a vibration as well.

Thanks. Your references to cork gaskets and shims explains a lot.

I'll go back and fit the bell sleeve to the transmission before I reinstall the u joint and soak the cork gasket in some wd-40 before tightening the whole thing down.

every time I get confident...

Good advice so far.

If you weren't getting a vibration before the clutch and U-Joint replacement, then I would suspect (after the U-Joint inspection that you:

a. Have not sealed the bell back up properly.

b. The clutch is causing the vibration or

c. The front yoke is loose,

d. A combination of them.

What the others meant by "rotation" of the bell was "move" and "movement." It doesn't rotate. (Sorry, fellows, I couldn't help the nitpicking. Please forgive me. )

Anyhow get yourself some thin gasket material (you can cut your own) and redo the gaskets with the four holes, and get a better seal material (Large O-Ring from Caterpillar (Cat), or some other source, and snug up the sleeve. The bell should be snug but, as Gene says, to tight enough that it won't smoothly flex when you try to move it with your hand on the sleeve. I got an O-ring for the sleeve from Cat and it works great.

You may want to run the car in gear with the access plate removed and the right rear wheel safely off the ground. See if you can feel a vibration preponderantly at the sleeve but not the transmission. The rotating U-Joint should flex smoothly in a wide variety of angles up to its limit of stop angle.

Good luck with it,
Charlie

If the clutch parts are causing the vibration the vibration will occur with the transmission in neutral and the car not moving....by reving up the engine.

Didn't think it was the u-joint. It has a certain amount of play...I think all cars do... it's a combo of things... Yoke, etc...