TH350 leaks front/real seals,wont stop

[turbojack]

Got a freind with a TH350 from speedway (bout 18 yrs ago) only got 15K miles on it (its in a 46 ford street rod). We`ve tried everything we can think of to stop the drips from the front seal (at the convertor) and the rear seal (at the drive shaft) .It only leaks when it sits for several weeks.The local trans guys say there is not a "new more improved" type seal made for these trans,,I`m not so sure he`s right,,,Is there a better ,improved seal made for these TH350 to stop the leakage drips,if so,whats the brand name and where do I get em? We even tried a bottle of stop leak,it didnt work either-------Jack

 

[bluettype]

did you check the driveshaft yoke for nicks or grooves, also the convertor?

 

[49-blues]

Without getting new seals i think you re limited to what you can do, i have used a sleeve which slides on the shaft of the rear pinion yoke which gives you a new surface closer to the seal which stopped my drip, so you maybe able to slide one on your driveshaft which should work, as far as the front not sure if they have the right size sleeve-i believe this is a trw part available in truck or car part stores,it was about $8.00.-it just gets tapped on the shaft with a deep socket or similar tool.

 

[Steve V]

check the pump bushing and tail shaft bushing,with new seals and good bushings it shouldn't leak.

 

[comp]

check the pump bushing and tail shaft bushing,with new seals and good bushings it shouldn't leak.

i agree,,, have seen the pump gasket/seal bleed a little from inbetween the pump and case after sitting

 

[turbojack]

th350 drips after setting

Yeah,done all that(BRAND NEW CONVERTOR AND YOKE),but my main question is,are there any seals made for the TH350 that are made of superior quality,you know,like the the neoprene seals made for the newer ac systems,some material that doesnt dry out after time.It looks like these seals just have to get wet again after setting to swell up and stop leaking,anybody ever hear of such a thing?

 

[Steve V]

Not trying to be a smart ass,but if you have replaced all the seals/gaskets and bushings it won't leak. Something is wrong some where. Superior seals aren't made or needed.

When the trans sits the TC bleeds down etc. It maybe the pump gasket or o rings or the washers on the pump bolts.

 

[bison]

There are no superior seals. Either the converter pump drive is damaged, the front seal is improperly installed,torn, out of round, the pump bushing is up against the seal(this would leak more than ever when the converter is spinning), the yoke is damaged, or the seal is not round, torn, or improperly installed. I use an anaerobic sealant on the outside of the seals to get a good seal since a lot of seal bores are scored from careless builders pryiong out with screwdrivers and they leave a leak path. The sealant always takes care of that as long as there are no other issues like the ones i listed. Are you positive its the seals you stated? Because those typically wont continually leak when the car is sitting still on level ground.

 

[turbojack]

TH350 leaks

After listenting to all you guys,I`m going to go over this with a fine tooth comb,it certainly looks like we`re missing somthig here.In the past when I run up against these gremlin things,it almost allways turns out to be somthing real easy,I`m just not looking in the right spots,,,thanks guys,,Jack