Help with tranny overdrive leaking

[AUSMHLY]

Has anyone had any luck minimizing the leakage from the transmission and overdrive in a BJ8?

What thickness' are the gaskets suppose to be?
1. Transmission Gasket, case to clutch housing.
2. Overdrive Gasket, overdrive to gearbox.
3. Overdrive Gasket, plate to casing.

I believe the original overdrive gasket, plate to casing was red colored. I think it may have been thicker than the other two gaskets? (This is the area, gasket that leaks the most.)

I think (and that usually gets me in trouble)that the gaskets moss and BV sells are all 1/64 tan colored. (for 1,2 and 3)

I've shopped locally for a thicker make your own gasket. What I've found is a roll by NEA products. Description: Asbestos free, high temperature gasket material. #1967. Size 12"x 20"x 1/16" Easy to cut / E-Z to use for automotive applications such as EGR and carburetor mounting gaskets, water pumps, water outlets, oil pumps, fuel pumps, etc. Do not exceed 350 degrees F.

My Transmission/overdrive mechanic and I are spending a lot of time r&r the unit. Seems the problem is the aftermarket gears. Seems to shift ok on the bench, but not when under load in the car.

Current problem, 1st and 2nd pop out. Tried using washers between the selector shaft ball and spring, and one washer in the layshaft. Lots of pressure to get it in, and a nice click sound saying it's in. Then it slowly moves itself towards neutral and pops out of gear. We've ordered Denis Welsh's first gear with sliding hub. (ouch, that's pretty penny).

Anyway, back to the leakage. I'm still leaking, after using new gaskets. The current gaskets don't seem to be doing their job. My feeling is they are not thick enough, or the leak is from the studs/bolts. I've heard some people say try using "The Right Stuff" sealant. https://www.permatex.com/brand_right_stuff.htm

My mechanic and I are leery of using something new. Going with the tried and true paper gasket. But then, it may simply be tried and true that they leak. Try something new? Has anyone used The Right Stuff on the tyranny/overdrive?

Cheers, Roger

 

[Randy Forbes]

Try this:

You'll never look back :wink:

 

[AUSMHLY]

Hey Randy,
Try this, as in you use it?

 

[Randy Forbes]

Yes, but I don't <span style="font-style: italic">eliminate</span> the gaskets, I still use them with just the slightest film of sealant. Applied properly, you'll barely see any squeezed out from the mating flanges.

At the present time, my car doesn't have an overdrive (MGC xmsn fitted) but I use that flange sealant on BMW differentials frequently (closest thing I have to a day-job is working on M Coupes/Rdstrs at home__see: www.rfdm.com/gallery).