The Official 356Talk Forum

I have transmission fluid weeping out around the studs on the axle tube flange (6 hole) and the differential cover (8 hole).
Is there any shortcut to replacing the gaskets on both? '58 "A",644 transmission.
The engine is currently out, so it seems to be a good time to address the issue.
Any suggestion would be appreciated.

Thanks

Put a baker's tray and some newspaper under it.

Try to wipe off the oil from the studs and plates as best as possible. Get Permatex's Stop Leak (by Loctite) from a nearby FLAPS.
It's a 4-oz. blue w/white can and it sprays a silicon sealant which 'kinda' coagulates w/the minor left-oiver oil leak--it was suggested
by the late RIP Mike Robbins and it worked for me several times over the years; You may need to do it a second time.

Be sure to blow out the plastic nozzle/tube to prevent clogging when finished, or it's a job to unplug it after it cures.

When I used to build custom yachts we used to mix acetone with rubbing alcohol to use as a heavy duty cleaner. Acetone will clean just about anything and the alcohol prevents it from evaporating immediately.

Careful what you get it on - it melts plastic and other stuff sometimes -

Here’s a video of the spray on sealant that actually can work sometimes
https://m.youtube.com/watch?v=Ka4eEViClcw

Thanks to you all for the advice & suggestions.

Dick, I didn't know that the spray Permatex product existed. I'm definitely going to give it a try.

John, The link to the video and the recipe for the cleaner were much appreciated.

Robert, When I bought my first 356 in the 70's, I think that set-up came with it from the previous owner, but since my friends have acquired nicer driveways as their incomes have increased, I am looking for a solution which might eliminate, or lessen, the tell-tale signs that my car was there.
BTW, a large baker's tray filled with newspaper sits under my car in the garage as I type.

Love this site. Thanks again

The spray Permatex 82099 works, I just did a transaxle that was leaking on an old split case VW, a friend brought it over, we cleaned the case really well with brake clean, and then used Simple Green, let it dry. Since the spray has a tendency to go on wider than we wanted, masked off the seam leaving about 3/8" gap for the sealer. Sprayed on 4 coats with an hour wait in between coats, then scored the sealer along the tape and pulled the tape off. It took about 2 days to full dry to where it wasn't tacky. But, so far no leaks and while if look close you can see the sealer it's better than having Sweepco drips on the case and floor. I went to find some more and two local parts stores said it wasn't in their computer anymore, so ordered an extra from Amazon $13.39 free shipping, maybe something about California compliances.

If the oil is leaking past the threads on the studs and not the perimeter gasket, special sealing washers with a rubber insert in the center work really well. An easy bolt on fix with no sealant necessary. There are a few varieties of these, the one that has worked best for me are available from McMaster Carr, part number 93781A037.

Leaks around the axle flange to side cover junction are common and more difficult to repair, and most likely coming from the gasket itself.

If the leak is thru the threads of a bolt or stud, I use a length of cotton kite string that has been passed through a glob of Permatex #2 non-hardening sealer. Wrap the threads a few times with the lightly coated string, tighten up the washer and nut, then trim the string. My Grandfather used this technique back in his garage and after 100 years still works. Plus it's easy to clean off with a small wire brush.

More great ideas.....thanks
I've just finished cleaning one side, so will let it sit for a few hours to see if I can tell for sure from where the leaks are coming.

...in times past, I have found a thick washer, or thick nut, and counter sunk it, to accept an O'ring, similar to the post B washers, at the 6 case through studs, to help effect a seal.

At parting surfaces lines, I've also cleaned, and semi-grooved the interface, and applied a coat of JB. Weld, for a seal, and had it last a couple of hundred hours.

When in RVN, we patched bullet holes in the Bell composite rotor blades, with A-4 Metal Set, amazingly close to the J.B. Weld, but meeting a Mil Spec... with a "Coke can" thin aluminum patch, top & bottom, ...but I doubt that procedure, was in the maintenance manual. It was a "field expedient"... the Bell rotor blades, were made of Adam's " Unobtanium", as were the M-60 barrels. I hadn't thought of that in a while,