Classic/Antique Car Repair/1957 chevy power glide transmission
Any idea as to the cause of the transmission blowing fluid out of the filler tube?
I'm not a Powerglide expert, but since nobody else is helping you, I'll give it a stab. First off, Powerglides are some of the strongest transmissions known to man, even for an old MOPAR guy like me. They are still being used by professional drag racers TODAY!
Second, as in most things mechanical, start eliminating the simplest causes first before moving on to the more complex. In this case, has the transmission fluid been overfilled? Transmission fluid expands when it's warm, that's why Chevy says to park the car on level ground, checking the fluid warm, engine running and transmission in PARK. Beyond this, there are internal transmission failures that can pressurize fluid but I'd rather a Powerglide EXPERT take the lead from here on out.
Fortunately, there is help locally. There should be one or both Classic Chevy or Tri-5 clubs in your area. Ask either one and you'll find a wealth of expertise and information about your car. You might even get one of them to look at the car for you!!
Best of luck. I'm sorry I couldn't be more helpful.