51' Olds Hydra-Matic trouble

[Guest KCOlds]

Hi, new to this forum. I'm getting ready to tear down / partially disassemble my hydramatic and am in search of any other thoughts on my issue before I do. This started last fall and I have yet to resolve it. I posted this in the classic olds forum last fall and received some much appreciated feedback. Just looking for any other hydramatic tips or suggestions before I disassemble this thing.

1951 Olds hydramatic: driven out of drive way down the street and back first time in years. ( 10+ ?) Shifted late and hard. (nothing new) Pulled back into drive to drop the pan drain torus and clean screen, clean valve body... before I do I back up once and it sticks in reverse and will not let go.

Reverse only... forward gears engage but will not move forward, bogs down as if under load (resisting reverse cone clutch is my guess) In neutral reving up, car inches forward a bit. No pushing the car forward in neutral unless cranking or idling.

I've since drained pan, torus and cleaned screen, valve body (several times) checked linkage, checked the movement of the servos with air... I'm about to pull the tail shaft to remove the reverse clutch assembly. Any other thoughts?

Much appreciated.

[Pete Phillips]

Put a quart of B-12 ChemTool in with the transmission fluid and run it through all gears. Jack up the rear end so the fluid all goes to front of transmission; do the same at front of car so fluid all goes to rear. This is while car is idling. Move lever through all gears and let it run or idle when you do this. The B-12 will soften up the seals and make them more pliable. Sounds like you have brittle seals or 0-rings which are letting fluid into two different gears or pathways at once, locking up the transmission. This is typical when an old car has sat for many years. It may not work all the time, but it has for me in the past on a '54 Olds 98, and is cheaper and quicker than pulling the transmission apart. Don't worry about overfilling the transmission fluid. The B-12 eventually evaporates.

Pete Phillips

Leonard, TX

[Guest KCOlds]

I did use Seafoam Trans-tune with the rear wheels jacked up just off the ground. I may for look that Chemtool. I think it circulated though I didn't try and elevate the car back and forth. It idled for a while up to temperature and tried to work through the gears.

[Guest KCOlds]

> Throttle rod out of adjustment < After several valve body tear downs (last fall) I've discovered tonight that the TV rod was way to low. Not sure why it worked before. I suppose the rear motors could have thrown things off. I've had the linkage off a few times after rebuilding the carbs. Maybe I threw it out then. After tightening it towards carbs, I now have drive gears. Still needs adjustment but at least it's shifting now. Anyway, thanks for your tip on the Chemtool.