Also my first thought. Transmission output shaft was leaking, due to a loose drive pulley. I R&R'd the primary cover twice before the pulley moved out and hit the inner primary.

The MoCo was using something similar to pipe dope when I got my 93. And the primary plug was never a great design as it is merely a set screw, whereas the other plugs have o-rings to help seal them. A number of years back, I started using Permatex liquid teflon on all three drain plugs and haven't had any leaks.

 

It's a 1/8-27 NPT plug I believe.

 

If the threads are worn enough to leak but still ok to tighten securely , i would try a seal
washer of the correct size . Auto parts stores have them in all types and sizes as replacements for the washers on the crankcase oil drain plugs. Should solve the problem for a buck or two.

 

its a straight plug....how do u do that???????

 

Ok. if its a straight tapered threaded plug , try 3M Scotch Gaurd #800 . Its never failed me yet . Comes in a squeese tube $8.00 at any commercial plumbing supply store.

 

how about a step by step on how to use this product....sounds awesome....pics would help too......can u git this at walmart??? please help....

 

Any squeeze tube sealer works the same way.
Take out the plug fill the threads with the sealant of your choice then screw the plug back in.

 

I finally got it sealed. I was talking to one of them "old boys" that hang out at our local machine shop, and he told me to try "finger nail polish"(of all things) and some teflon tape. I put some nail polish (purple of all colors, the only color the ol lady would let go), on the threads and then some tape and then some more polish, and damned if it didn't work. Up to that point i had tried some Loctite with teflon, teflon tape, some plumbers dope, and about any combination of them, and still had the dreaded drip. But three days later and a few hundred miles still no drip. Sometimes it pays to talk them old boys.

 

Sounds like your next venture into changing primary oil should be started using a size over tap.