QuestionQUESTION: Hi Dick - I recently bought a '57 Chevy convertible that had been in storage for approximately 30 years. After changing the fuel pump and filter, and installing new points and distributor cap, the engine started right up. However, the Powerglide transmission will not engage in drive or reverse. The people I bought the car from insisted that it was driveable when they placed it in storage, so I would venture that the valve body pressure regulator or manual valves are stuck. I've tried adding a tranny cleaner and running the car for 20 minutes while shifting from neutral to drive to reverse, to no avail. Do you have any suggestions to free up the valve(s) without pulling the transmission and disassembling the unit?
Thanks for your help. Jack
ANSWER: After that many years, the old transmission fluid is very likely gummy enough that the spool valves are sticking in their bores - the clearances are very tight in those valves - and they cannot tolerate even a tiny bit if stickiness in the fluid.
The good new is you don't have to disassemble the transmission to fix this - you can remove the valve body by taking the pan down, but you do have to know what you are doing or you will wind up with a nightmare trying to put it back up when you have it cleaned out. Before you do this, buy a rebuilders manual or better yet a factory shop manual which will give you step by step directions as to how to remove the valve body. Once you get it out, I advise you to take it to a transmission shop that has experience with the old cast iron powerglide and ask them to clean out the valve body for you. You can do this yourself, but again, if you don't have experience taking apart and re-assembling valve bodies, I think you'd best let a pro do it. There are hundreds of parts in there, and a jillion tiny springs etc, and you cannot take a chance on getting them mixed up!
Dick
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QUESTION: Hi Dick -
Thanks for the quick response. However, unfortunately, the cast iron Powerglides were not equipped with a pan. The pan was incorporated later, when Chevrolet changed the casing to aluminum. Sounds like I don't have an alternative to removing and disassembling the transmission to get to the valve body, which is bolted to the converter bell housing. Thanks, anyway. Jack
ANSWER: Sorry, you're right! I should have opened the book and read a bit rather than trusting my memory. It's been too long!
Dick
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QUESTION: That's okay, Dick. I appreciate the response. I was hoping that there was some possible way to get to those potentially sticky valves (because I didn't remember if there was another way....LOL). Take care. Jack
AnswerI understand. I don't think there is any solvent or detergent that will help. I just finished solving the exact same situation on a 51 Packard that had not been driven for 16 years. In this case, I dropped the valve body out and soaked it in lacquer thinner and acetone for a week, and still I had to drive out the spool valves from the bores with a wooden dowel and clean up the bores with a toothbrush dipped in acetone to get the crud out before they would move smoothly. Now it shifts fine.
Good luck with the Chevy.
Dick
