TH 350 leak
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Joined: Oct 2002
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From: Wanganui NZ
TH 350 leak
1977 Corvette
I have a bad leak in my TH350 auto,i like drive it on a saturday or a sunday and it seems to start leaking around wednesday,when it has been sitting for 3 or 4 days.Its had a full rebuild less than 2 months ago.Seems to be leaking from either the dipstick area or that corner of the sump gasket .Its a steady drip and the pool of trans fluid on my garage is huge,it seems like its gonna drop all its fluid. Any ideas anyone ??? :rolleyes:
[Modified by New-Zealander, 1:28 AM 11/3/2002]
I have a bad leak in my TH350 auto,i like drive it on a saturday or a sunday and it seems to start leaking around wednesday,when it has been sitting for 3 or 4 days.Its had a full rebuild less than 2 months ago.Seems to be leaking from either the dipstick area or that corner of the sump gasket .Its a steady drip and the pool of trans fluid on my garage is huge,it seems like its gonna drop all its fluid. Any ideas anyone ??? :rolleyes:
[Modified by New-Zealander, 1:28 AM 11/3/2002]
Race Director
Joined: Feb 2000
Posts: 12,431
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From: CT
Re: TH 350 leak (New-Zealander)
if there is to much fluid in the tranny it will force its way out the pan gasket when you drive it. happend to me once. as soon as i got on the highway, there was smoke every where from the fluid hitting the exhaust. :crazy:
Le Mans Master
Joined: Aug 2000
Posts: 9,662
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From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: TH 350 leak (New-Zealander)
There are a number of places that the TH350 can leak from, dipstick o-ring is a good primary suspect. If that doesn't do the trick then start looking at the vacuum modulator, it is held in by a "Y" shaped retainer and also has an o-ring that can leak. Another place is the governor cover, it is held on by four small headed bolts, and let's not forget the speedometer cable and Paul79's favorite source of a tranny leak the shift shaft.
The best advice I was given when looking for the leaks on my tranny, just replace everything! That's basically what I did, I ordered a reseal kit from http://www.bulkparts.com I got a complete rebuild seal kit for my TH400 for $16.00. Even with the postage to New Zealand it would still be a bargin. It included all the gaskets and seals for my transmission, I dropped the transmission and replaced them all. The transmission is tight as a drum now, although I haven't driven the car, it has set full of fluid for about 3 weeks, and hasn't lost leaked a bit. I guess I'll find out after next weekend, when I should finally get the car back on the road.
Good luck on finding your leak.
The best advice I was given when looking for the leaks on my tranny, just replace everything! That's basically what I did, I ordered a reseal kit from http://www.bulkparts.com I got a complete rebuild seal kit for my TH400 for $16.00. Even with the postage to New Zealand it would still be a bargin. It included all the gaskets and seals for my transmission, I dropped the transmission and replaced them all. The transmission is tight as a drum now, although I haven't driven the car, it has set full of fluid for about 3 weeks, and hasn't lost leaked a bit. I guess I'll find out after next weekend, when I should finally get the car back on the road.
Good luck on finding your leak.
