Bellhousing Leak

[73Swinger18]

My 904 leaks a little at the bottom of the bellhousing after it sits for five or more days. It's a fresh rebuild/reseal and doesn't leak a drop if I drive it regularly. I've read about the converter leaking back into the transmission and coming out a vent. Not sure if this is what I'm experiencing or something else. Is there anything I can do to prevent it? Thanks for the help!

 

[RustyRatRod]

The bellhousing doesn't leak. You have one of the following. A cracked converter snout or hole or crack in the converter. A bad converter front pump seal or a bad front pump o ring seal. Those are the only places a leak can occur. If it is coming out of the vent, you have other issues.

 

[73Swinger18]

The bellhousing doesn't leak. You have one of the following. A cracked converter snout or hole or crack in the converter. A bad converter front pump seal or a bad front pump o ring seal. Those are the only places a leak can occur. If it is coming out of the vent, you have other issues.

Wouldn't all of these leak dynamically? If I drive it every couple of days, it's bone dry.

 

[RustyRatRod]

Wouldn't all of these leak dynamically? If I drive it every couple of days, it's bone dry.

No,not unless something was wrong.

 

[d55dave]

Leaking statically after sitting for a few days is usually the shifter shaft or kickdown shaft seal (above the trans pan rail on the drivers side). They are one of the more common leaks on the torqueflites. The fluid could drool down and hang off the bottom of the bellhousing area and appear as you say. When parked the fluid in the converter slowly drains back into the pan, over filling it and leaking out the seal(s). The solution is to drop the pan and valvebody to change the seals.

 

[73Swinger18]

Leaking statically after sitting for a few days is usually the shifter shaft or kickdown shaft seal (above the trans pan rail on the drivers side). They are one of the more common leaks on the torqueflites. The fluid could drool down and hang off the bottom of the bellhousing area and appear as you say. When parked the fluid in the converter slowly drains back into the pan, over filling it and leaking out the seal(s). The solution is to drop the pan and valvebody to change the seals.

The fluid is on the bottom interior of the bellhousing. It's only a few drops I have seen twice now and only after not driving it for several days. It seems like it only happens after I drive it after prolonged sitting. I could leave it there for two weeks and not a drop will touch the ground. Take it for a drive after sitting and park it overnight and there will be a few drops. After cleaning it up, it will stay dry until I let her sit again.

 

[RedFish]

Just the opposite of my 67. Seal won't leak much at all sitting ( not a drop after clean up over several days wait ). Start it up and drip drip drip. In my experience, That's just the way shaft seals act. Fluid pressure behind it can tighten it when the material is new and flexible. that fluid passes a old hardened lip seal. Some leak when the shaft stands and lays down on the lip. Some leak at their metal to metal perimeter too. How it was installed is sometimes the fault there. Improper tool is a gamble.
We all agree where this shaft seal is just sux! Good luck with yours.

 

[oldkimmer]

I had 1 with a pump bolt gasket do exactually what ur describing. Kim

 

[AJ/FormS]

I'll go with Kim

There is a valve in the VB that is supposed to prevent the TC drainback.
I've had a 904 with a cracked hub. It gave no symptoms at all.

 

[73Swinger18]

Here's the follow-up. I took the car for a long drive on the freeway and got the transmission fluid nice and hot, then checked the fluid level. It was about a quarter inch above the fill line. All other times I checked the fluid, it was after a short trip and never really got the fluid hot enough to get an accurate reading. I drained some fluid until it was right at the fill line and I haven't had any leaks since. I think it was the over servicing that caused the fluid to come out of the vent. The 3-5 days of sitting was just a coincidence.

 

[d55dave]

Perfect! It is nice when the solution is so simple. Could have even been misting out the vent and then getting slung around inside the bell by the converter. After being parked it slowly ran down to drip out.