Rebuilt 1957 Buick Dynaflow spurts fluid through fill tube when shifted in reverse.

[1957buickjim]

I'm in the process of finishing my restoration of my 1957 Buick Estate Wagon, and in checking out the transmission (which has been rebuilt) when I have been shifting into reverse (and having to rev the engine to get it to move) the fluid shoots out of the filler neck all over the exhaust manifold and frame. Doesn't do it in Drive and haven't tested Low yet. I have installed an external transmission oil cooler in series with the radiator integral oil cooler, as I want to be able to tow my Shasta AirFlyte with the wagon. 

Any ideas as to why the trans would blow back fluid only in reverse? As a side note, I have only run the car in the driveway only for 20-30 minutes, not taken it on the road for loading of the transmission. Thanks in advance for any insights on how to correct this. 

[lancemb]

5 hours ago, 1957buickjim said:

I'm in the process of finishing my restoration of my 1957 Buick Estate Wagon, and in checking out the transmission (which has been rebuilt) when I have been shifting into reverse (and having to rev the engine to get it to move) the fluid shoots out of the filler neck all over the exhaust manifold and frame. Doesn't do it in Drive and haven't tested Low yet. I have installed an external transmission oil cooler in series with the radiator integral oil cooler, as I want to be able to tow my Shasta AirFlyte with the wagon. 

Any ideas as to why the trans would blow back fluid only in reverse? As a side note, I have only run the car in the driveway only for 20-30 minutes, not taken it on the road for loading of the transmission. Thanks in advance for any insights on how to correct this. 

Have you called your rebuilder for insights?

[old-tank]

Air in the torque converter; overfilled?

For now pull the dipstick and put some heater hose over the tranny fill and into a jug and run it!  If it does not stop your next project is to pull it after doing pressure tests as outlined in the service manual.

(mine does that after prolonged sitting:  fluid in the torque converter drains into the pan overfilling it; upon starting the fluid is pumped into the torque converter displacing air which blows fluid out the dipstick tube.

[1957buickjim]

Lance, I did call Jim Hughes and he said to drive it for a good ten miles. As soon as I get the brakes finalized I’m gonna do that. 
 

Willie, that’s a darn good idea! I will try that before I head out on a drive. The transmission was newly rebuilt and dry when I put the rebuilt engine in and broke it in. I added probably 13-14 quarts of fluid, to make sure torque converter was filled which probably a bit too much! I’ll let it

overflow with the heater hose system until it either stops or I need to go to your plan B. Thanks for the insight gents. I’ll keep you posted. 

[old-tank]

Check the vent if equipped at the top rear of the transmission.

[pfloro]

9 hours ago, 1957buickjim said:

(and having to rev the engine to get it to move)

This is quite puzzling and doesn't seem right (unless the converter has partially drained back)...

 

If the brakes aren't dragging and with minimal throttle, shouldn't the car creep in Drive, Low, and Reverse...?  

 

I've never driven a Dynaflow so perhaps this is normal. (?)

 

"The Car Which Shifts a Thousand Ways..!"

 

Paul

 

 

Edited June 2, 2022 by pfloro (see edit history)

[NailheadBob]

I like your thinking @old-tank , I had a 1962 Electra that if parked on incline and sat for more than a couple of days, fluid would slowly drip out the vent tube on top of transmission.

 

Bob

[60FlatTop]

For a test you could make it blow fluid again and check the temperature with an infrared thermometer. It could be boiling inside the transmission after 10 minutes of some internal problem.

I have seen transmission fluid blow out the tube due to dragging brakes in the past, but you haven't driven yet. Even checking the pan temperature as it warms might help. Don't rule out anything unless you test it.

[EmTee]

Where are you located?