1952 Cadillac Series 75

[drhach]

There's no graceful way for getting a transmission in and out of a car when it's on jackstands. I've done it many times. It always sucks. Keep your kids away because you will be swearing. 

[Fleetwood Meadow]

Well I was hoping for a more definite answer.. I took off the torus and looked at the front seal. It looks new. I see no rips or obvious problems with it. The seal for the flywheel was not ruptured or leaking before I unbolted the torus cover. Neither was the drain plug. Since the rupture happened after revving the engine is there a pressure relief spring/valve I should check next?

[Fleetwood Meadow]

[Roger Zimmermann]

The Hydramatic from 1956 to 1963 are more or less my "specialty". I don't know the previous models, but something is looking similar: the torus cover assembly from your last picture.

The hub is most probably welded to the torus. 

Last year I had a problem with a '56 Hydramatic: there was a massive oil leak.I replaced the seal, but the leak was still there. After some message exchange with people I know, I did a leak test with the torus cover assembled with the flywheel, inflating the whole with air. To my relief, there was a leak at the weld. A small local shop rewelded the neck; the issue was solved.

The first picture is the assembly with compressed air ; the second picture is showing the new weld.

I don't know if the previous Hydramatic transmissions had this issue. If you can test it you are then sure that tho problem is at another place.

[pfloro]

8 hours ago, Roger Zimmermann said:

I don't know the previous models, but something is looking similar: the torus cover assembly from your last picture.  The hub is most probably welded to the torus. 

Roger is on to something here. 

 

The new "controlled coupling" Hydra-Matic debuted in 1956 and dropped out in about 1964.  Although the internals of the "Model 315" were quite different from the 1st generation HM, I suspect the fluid coupling was very similiar.  Neither design used a torque converter (that arrived in 1964 with the Turbo Hydramatic 400).

 

I would reassemble your fluid coupling, take it to the shop which rebuilt your HM in 2022, and have them inspect & pressure test it.  I could see how fluid would be thrown out and away from a quickly spinning coupling.  Maybe the "tink-tink-tink" sound you heard was the hub weld giving way...

 

FYI:  Based on the GM division, the "controlled coupling" HM was known by various marketing names...  Olds called it "Jetaway", Pontiac called it "Strato-flight" or "Super Hydra-Matic", and at Cadillac, it was known as the "Hydra-Matic 315"... 

 

Paul

Edited August 18 by pfloro (see edit history)