Darn gaskets!!

[TurboDave]

My trouble with pan gaskets started a few years ago. Once was the time the only time the tranny would leak is when I'd pound on the car real hard, several times, didn't leak if the car was driven normally. I should have left well enough alone.
I decided to change the tranny pan gasket last spring, and installed a cork gasket. that leaked/seaped any time, figured I did something wrong.
Took it to a local tranny shop that specializes is high performance applications and they installed one those composite, paper like gaskets. It leaked!
Took it back to them, and they replaced that with a good cork gasket. It leaked! argg! There seems to be a tiny bit of seapage all around the gasket, but primarily from 2 or 3 specific bolts. ?????
I'm tired of this so my last resort is to pull the pan myself again, and this time do it with "The Right Stuff" form a gasket.
Will this work I wonder. Sure hope so! I'm out of ideas.

I thought the bolts were all supposed to be "blind", but this time I'm going to have to try and see if the 2 or 3 suspects may not be as blind as I thought, maybe some small cracks developed around the bolt bosses.

I don't know, I'm stumped.

Oh, BTW, its a deep aluminum pan. last inspection it checked flat and no visible craks.

 

[TurboTdr3.8]

You sure it not leaking at the shift shaft seal and leaking down when it sits making it look like the pan

 

['75]

You sure it not leaking at the shift shaft seal and leaking down when it sits making it look like the pan

I agree, had that issue before.

 

[1KWIKSIX]

Is this an aluminum pan or the factory tin pan?
Is your pan surface flat? check with a machinists level or straight edge.
Also be sure to follow the recommended diagonal bolt torque sequence when tightening up the pan.
Not much torque needed for these gaskets.

I finally found my leak by using UV dye in the transmission fluid with a black light....found it was actually coming from the electrical solenoid pass thru connector on the side of the transmission. Guess the "O"ring wasn't sealing properly.
Got a replacement pass thru connector from Dennis Kirban & that fixed my problem!

http://www.kirbanperformance.com/product/44054/ELECTRICAL SOLENOID PASS-THROUGH CONNECTOR WITH O-RING for 200-4R Transmission #7486.html

 

[robzombie]

Dave I used to have the same problems that you did.

I tried everything to no avail. and when I had my trans rebuilt Lonnie used one of those there high falutin composite gaskets.

He took the pan down at least three times and didn't even clean the trans fluid off the gasket when he put it back up.
He told me it would seal even if he left fluid on the gasket and sure as heck it did.

The only thing is that after driving it a few months and a lot of abuse it started to weep, not so much a leak but wet/damp with fluid.

I put thread sealer on the bolts and it stopped the weeping. I wouldn't use any cork gasket as they leak every time and I've had the composite gaskets on there two years now and they are the same ones that Lonnie put on there and the pan was down multiple times with no issues.

I could look up the pat# of the gasket if you want or you could call Lonnie and he will sell you one or give you the number of the gasket and confirm what I've just posted, except for the thread sealer part.

I tried that to see if it was somehow leaking past the bolt threads and it worked. Whether it was getting past the gasket to the bolts or some other reason I don't know.

All I know is that the pan is dry now and I'm not touching it until it leaks or I change the filter.

BTW I'm using a deep sump aluminum pan also.

I'm not saying that this will solve your problem but it did mine.

Hope you get it straight as it's a pain in the azz trying to stop leaks on these cars. At least for me it is.

 

[TurboDave]

You sure it not leaking at the shift shaft seal and leaking down when it sits making it look like the pan

Checked that. Not leaking there.

 

[bison]

Time to pressure test it. I've done it
before to find or eliminate leaks sources.


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[TurboDave]

Time to pressure test it. I've done it
before to find or eliminate leaks sources.


Sent from my iPhone using Tapatalk

That would be nice but I don't have the facilities or equipment.
I'm most worried about the fact that three bolts were soaked. I thought all bolt holes were supposed to be blind.

 

[turbobitt]

Selector shaft seal, TV cable seal, filler tube seal, pump gasket, pump seal, speedo gear seal, and finally trans vent problems can all find its way down to the pan.
AG.

 

[INEEDAGN]

We used cork gaskets almost exclusively back in my trans shop days, occasionally the paper style (memory is killing me on what they were called). Never rubber unless it already had one of those molded rubber reusable gaskets. Torqued to 8 ft lbs and any time we had problems we always found a different culprit. Personally I love cork or paper gaskets for just about everything.

Holes should all be blind but if someone put too long of bolt in it and cracked it or if it had a casting flaw, its possible....

 

[INEEDAGN]

Also very possible for the case to be cracked somewhere or even be cast wrong. Seen stranger things happen..

 

[SS/GN]

When I do a pan I always tap the bolt hole with a large punch to push it back down. if you don't the gasket never gets compressed evenly.

 

[Nick Micale]

You sure it not leaking at the shift shaft seal and leaking down when it sits making it look like the pan

Seen that many times lately as that seal is almost never replaced on a rebuild.

Also the seal on the electrical connector can also weep fluid, and it will run around the pan to the low side and appear as a gasket leaking.

 

[robzombie]

When I do a pan I always tap the bolt hole with a large punch to push it back down. if you don't the gasket never gets compressed evenly.

That only works on a steel pan which is a good idea and should be done to get a good even seal and compression of the gasket.

However he is using an aluminum pan which should be distortion free and won't warp/twist when properly torqued.

 

[INEEDAGN]

x2. On a steel pan, if the bolt hole flanges look even slightly warped upwards, you can rest the edge of the pan on a workbench and hold the round end of a ball peen hammer in each hole and give that hammer a good tap with a soft mallet to push them down. If it goes a little too far its no biggie as it will level out when torqued. But this isn't a steel pan.

 

[TurboDave]

Seen that many times lately as that seal is almost never replaced on a rebuild.

Also the seal on the electrical connector can also weep fluid, and it will run around the pan to the low side and appear as a gasket leaking.

They were carefully checked and showed no signs of leaking.
Ther is no fluid anywhere above the pan rail. Nor anything from the front pump area.

 

[bison]

Seen that many times lately as that seal is almost never replaced on a rebuild.

I always replace that seal when I have the Trans on the bench and have replaced it on several transmissions in the car because it was leaking.


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[SS/GN]

That only works on a steel pan which is a good idea and should be done to get a good even seal and compression of the gasket.

However he is using an aluminum pan which should be distortion free and won't warp/twist when properly torqued.

Oops I did not see the alum pan part