Torque Converter Draining Down...

[threewood]

So I noticed that a pool of trans fluid was forming under my 62 Belvedere (727 pushbutton trans). It was dripping from the parking cable box. I pulled the dipstick and it showed waaay overfull. Has to be the converter. Car sat for a while no drips, then plenty of drips. So I start the car up run it up to temp, check fluid, about a quart low. Top it off, fluid level in spec for hot. Go out this morning and no drips, fluid is on the line for cold temp.

What causes the torque converter to drain back to the case? Any specific seals? Just one of those things from sitting a while?

 

[Dave6T4]

Just one of those things from sitting a while. If it was driven every day, as designed 60 years ago, it would not be noticeable. What I have done, is install as deep an aftermarket pan as you can, with appropriate filter extension. In your case, push button transmission, make sure your filter and extension has 2 intake holes. Instead of filling deep pan with additional fluid, I just use the factory amount; 8 quarts (9 litres). Using the filter extension as a gauge, I remark new FULL and ADD levels by drilling small diameter holes on the dipstick. This gives your torque converter additional room to drain back to. I always start my car up in NEUTRAL and let it idle for a minute or so. This allows the converter to refill before trying to move the car.

 

[wagonman]

I just went through this 63 PB 727. Sonnax makes a V-body pressure control valve that addresses this issue among others. Mine would leak @ the Park housing and drain enough that car would not move, 3 Qts or so. Have to drop the VB to replace not a big deal. Also while out I drilled the plate in one hole for a better 1-2 shift. The leak is all but fixed but is still seeping from the cable crimp, needs a new cable. Also this trans was rebuilt by who knows who pretty much stock. It needs a better stall convertor A&A makes one for the 19 spline so I am saving to get one about $300.

 

[Dave6T4]

I just went through this 63 PB 727. Sonnax makes a V-body pressure control valve that addresses this issue among others. Mine would leak @ the Park housing and drain enough that car would not move, 3 Qts or so. Have to drop the VB to replace not a big deal. Also while out I drilled the plate in one hole for a better 1-2 shift. The leak is all but fixed but is still seeping from the cable crimp, needs a new cable. Also this trans was rebuilt by who knows who pretty much stock. It needs a better stall convertor A&A makes one for the 19 spline so I am saving to get one about $300.

View attachment 1317935

You can fix leaking cable crimps with shrink tubing. Pick a size that will slide down the cable and over the crimp. Heat it up with one of those little butane torches, and you are done. A tip from member DVW.

 

[khryslerkid]

You can fix leaking cable crimps with shrink tubing. Pick a size that will slide down the cable and over the crimp. Heat it up with one of those little butane torches, and you are done. A tip from member DVW.

Just make sure it's the shrink tube with the glue inside. The regular shrink tube doesn't work. AMHIK

Clean with parts cleaner thoroughly before applying.

Forgot to add...Home Depot had it in their electrical department. Different sizes also.

 

[threewood]

Thanks for the replies. My cable is fixed via glue and shrink wrap. No reproduction available. Just one tiny drip that I saw today, might be at the o ring at the cable. But not as bad as before.

The deeper pan is a good idea so I might go that route. The trans I rebuilt back in 2014ish but if I pull the pan I may get John Cope on the phone to see if he can do a partial kickdown valve body with street shifts. It already has a PTC converter.

 

[mopar 3 B]

Just kick a drip pan under it and forget it. They have done this for over 60 years.

 

[threewood]

Or I guess I'll start it more often lol

 

[MIKESPOLARA]

Interesting. I assumed my front seal on my 63 push button trans needed to be replaced as I have trans fluid leaking. However after reading this I may have the same problem from sitting for extended periods. I knew older transmissions such as early Chevy cast iron powerglides would do this but I never thought that such a new trans (63) would have this problem. I'm going to investigate it further. When I do drive the car to a show I'm concerned that I'll leave a bit of a puddle where I'm parked but it never does. Then when I drive back home it doesn't at first but after a few days it'll start to drip again. I'll clean it up and start it everyday to see if it stops leaking. The last 55 Chevy I had with a cast iron PG would be good if I started it weekly, let's see if that fixes this one.

 

[wagonman]

Interesting. I assumed my front seal on my 63 push button trans needed to be replaced as I have trans fluid leaking. However after reading this I may have the same problem from sitting for extended periods. I knew older transmissions such as early Chevy cast iron powerglides would do this but I never thought that such a new trans (63) would have this problem. I'm going to investigate it further. When I do drive the car to a show I'm concerned that I'll leave a bit of a puddle where I'm parked but it never does. Then when I drive back home it doesn't at first but after a few days it'll start to drip again. I'll clean it up and start it everyday to see if it stops leaking. The last 55 Chevy I had with a cast iron PG would be good if I started it weekly, let's see if that fixes this one.

Even My 92 Dodge Cummins is lazy after sitting and the 727 in the R/R as well. But they dont leak. I just pop them in neutral to get the juices flowing. Seems like a common problem even on newer rigs.

 

[5wndwcpe]

Pro Tip: If you want to pinpoint a trans leak, hose it down with brake cleaner or starting fluid (cheaper) to get rid of all the old leak evidence. The tear a paper towel in little pieces and stuff them all around the trans (cable, speedo, dipstick, shaft linkage etc.) Where ever the leak is, the paper towel will absorb it, turning red and rat out it's location.

 

[MIKESPOLARA]

Started my test today. Cleaned the spill up and ran the engine. I'll restart the car each day and see if the leak starts up again or not

 

[mopar 3 B]

If you're worried about the mess on the floor by some diapers for it.