Good morning..
A few years ago when I swapped engines, I replaced the converter seal while I had the engine out. It was leaking oil while running. Not a lot ,just enough to be annoying. After the R/R it still leaked ,no more or less. Im guessing the bushing is to blame. Can the bushing be replaced without removing the pump? Ive had a lot of things apart over the years,but never an auto. transmission. If I remove the pump, is there anything going to fly out and roll in a corner of the garage that I can't find or worse? Been putting this off for some time now. Thanks

 

Leaking while running is usually the front pump seal. Leaking from front area overnight is either the front pump o-ring or fluid running to the front looking like a front pump leak like; dip-stick tube o-ring, pan gasket, shift linkage shaft seal or kick down electrical conn. o-ring. In answer to your question, you can not replace the bushing (likely not the cause anyway) without removing the pump and dis-assembling it. If the trans has not been overhauled in the last ten years, I'd recommend leaving it to a professional to go through it with an overhaul kit or buy a manual and do it yourself. Keeping everything clean while rebuilding it is essential/critical. Determine if it's really leaking while running or not. Wipe it down and watch it. Make sure to use proper vehicle supports while under it. Suggest searching for threads about front transmission leaks for more opinions and information.
Jim

 

Thanks Jim I replaced the seal that the tq converter fits into. Where is the O ring seal?
Is that where the pump mounts on the trans. or on the attachment bolts ? I not sure the trans. has ever been rebuilt, Its a 76 and only had 69000 on it when I got it. No other issues other than that leak. I pressure wash the underside in the spring,oil seeps out the hole on the dust cover and gets blown back during the season. Maybe a pint / year.

 

The pump o-ring is the big one that goes around the pump itself. With the converter out, look inside the bellhousing. The big round thing in the middle is the pump. You have to use a puller set, like a pair of little slide hammers, to pull it from the transmission case. Around the perimeter is a big o-ring. That is probably the last place to leak, from my experience. I'd suspect any other seal, especially the filler tube or a loose cooling line.

 

Thanks for the reply casey. I replaced the O ring on the dipstick tube and attemped to tighten the lines. I'd like to rebuild the trans. myself, but not enough nerve. I've done my share of engines before but never an auto transmission. Looks like a trip to a tranny guy is in my future. Geeeze whats that gona cost???

 

If you only have the one leak, it's likely been overhauled before as they tend to develop many leaks over time at the various external seals. You need to remove the dust cover, wipe it down and watch it over time. Make sure you wipe everything so you can trace the fluid path. If you do this and it doesn't leak overnight, then start it up and see if the leak appears from the front seal area. It's possible that you didn't use a sealer around the seal perimeter when you installed it, didn't use a cleaner in seal seat prior to installing new seal with sealer, deformed the seal, dislodged the spring in the seal, or the converter hub was grooved at the sealing point from old hardened seal.
If you've rebuilt an engine then you can rebuild a trans. You can get a manual or look for online info., take your time, keep work area clean, rebuilding an auto trans of this vintage is pretty easy, one of the easiest. Flip the pump over and use the trans. case for re-alignment of the pump housing halves (prior to putting guts back in case and prior to putting on the pump o-ring). The only tools you may have to get are a bushing driver set (or use a machine shop) and a drum spring compressor (you can fab one or have a buddy to help compress spring cages for dis-assembly/assembly). Pump can be popped out without a puller using prying action (gently) once the trans. pan is off. Use the manual to identify areas of wear to look for (pump body, rev./high clutch drum etc.). Use a good quality gasket set/overhaul kit. Black paper pan gasket is a good indication the set is crap/cheap. The 2 bands can likely be re-used as can the steels unless they're warped or hot spotted. Put a black stripe modulator in it for firmer shifts. Oklahoma Transmission and Supply (OTS) is a good source among others.
Jim

 

If you can do the tranny removal and reinstallation, just pull it and take it to a good LOCAL tranny shop (not a national chain shop). They can either rebuild yours or swap yours with another already-built unit; and it's not that expensive with you doing the R&R.

If you do a lot of highway driving and you decide to swap the tranny, you might want to consider going to an overdrive trans. Gas mileage goes up about 20%, much easier on the engine, and much smoother and quieter for you.

There is some conversion expense and some part changes, but now's the time, if it would be a benefit to you.