83 SC Main seal leak tranny to engine question

[Reiver]

'83 SC with 279 k on the tranny with one refresh ( a few synchro's etc.) 33 k ago. I would assume the main seal was redone but am not sure.

After a spirited 190 mile drive the other day I noted a small line of oil from the tranny weep hole along the tranny halves going forward. I did not see any splatter anywhere else so assume dripped down after parking on my lift. Engine block and tranny are very clean so no issues about the origin.
It is stored in the up position so am often under it and noted this about an hour or so later after parking it.

I can drive, as I did today 40 + miles and nothing, maybe a little wetness around the weep hole if you use your finger....I have to go 70/80 plus miles to note any oil and it is a little seep from that weep hole. No splatter on the engine and no oil loss basically noted on the dipstick.

Is that normal for a failing main seal or could it be one of the two alloy plugs seeping in the tranny face behind the flywheel?

I would expect more of a leak but have no idea?

What are your experiences with this deal?

[yelcab1]

I have never seen the alloy plugs to leak by themselves. I have seen plenty of RMS leak. Years ago, changing oil brands to 20W50 Castrol stopped the leak but ... as of now, I would just pull the engine and change the seal if it bothers me that much.

[Reiver]

It always bothers me when I have a leak but not to the point of doing that yet.... I'll wait for a bit more clutch wear.

I am using Driven 20-50 presently but may try Liquimolly on the next as I've heard the same about that oil/seals.

[proporsche]

is it engine oil or trans oil ...smell it...
Ivan

[Reiver]

Originally Posted by proporsche

is it engine oil or trans oil ...smell it...
Ivan

Engine oil for sure with the sniff test....behind the flywheel as no clutch issues.

The seep is just a tad after a very long drive but I suspect most start this way. I notice because I store the 911 on a lift....most prob. don't notice until it leaves a puddle.

[proporsche]

ok, by bow you most likely check the engine top so that leaves you with the flywheel seal..There many types but the to go with is Elring which looks like this the other -no name to mention- our host has the right one

Ivan
https://cdn9.pelicanparts.com/catalog/images/SuperStock/999-113-426-41-INT.jpg

[Reiver]

Thanks, I've noted the differences in the seals out there and that is the one to buy.
My engine is very clean so no oil migrating from the top, it is from the seep hole for sure.

I'll get that seal but will hold off for a bit....get some more miles on the clutch so I can do the 'while you are there ' stuff.

[Rodsrsr]

Do not do the seal until you absolutely have to. I changed the RMS while the engine was out for a freshen up. Used the Victor Reinz and leaked like a faucet. Took the motor out again and replaced with Elring. Better now but still leaks after a long run and leaves a sizeable puddle the next morning. I plan on doing the job again in the spring but honestly don't know what I can do differently. I'm 100% confident I installed it correctly, even used the old seal flipped around to tap in. I should have never changed it in the first place.

[Reiver]

Originally Posted by Rodsrsr

Do not do the seal until you absolutely have to. I changed the RMS while the engine was out for a freshen up. Used the Victor Reinz and leaked like a faucet. Took the motor out again and replaced with Elring. Better now but still leaks after a long run and leaves a sizeable puddle the next morning. I plan on doing the job again in the spring but honestly don't know what I can do differently. I'm 100% confident I installed it correctly, even used the old seal flipped around to tap in. I should have never changed it in the first place.

When I do this I will use permatex 'the right stuff' as a sealant on the outside surface of the seal. Non hardening stuff and it has sealed impossible stuff for me.
I had a hot rod solid rear axle outside bearing seize on a burn out...spun the bearing and scored the area pretty badly. I used numerous seals with no joy and a guy told me to coat the seal with this and it worked permanently...for years, may still be as I sold it.
It is made for this and will work with oils/tranny fluid etc....some will say go dry but I have had too much luck with this stuff.

[Rodsrsr]

Thanks for the tip...I wish I knew if it was leaking from the outside or where the seal mates with the crankshaft, but this may eliminate at least the outside perimeter it that's the cause.

[Reiver]

Originally Posted by Rodsrsr

Thanks for the tip...I wish I knew if it was leaking from the outside or where the seal mates with the crankshaft, but this may eliminate at least the outside perimeter it that's the cause.

No way to know is there.... I won't pull this until it is a real leak...and there has to be nothing worse than doing the job, as you did, only to have the same issue. That would piss me off but I guess it happens.
I went thru about 4 different seals on the axle leak until I used that permatex product..and I used the same type seal that previously had leaked.

[cmcfaul]

I replaced mine when doing the clutch. Never used to leak, now about a drop a night and getting worse. Should have left it alone. will likely replace again and see what happens. No small task.

Chris
89 Carrera

[Reiver]

Originally Posted by cmcfaul

I replaced mine when doing the clutch. Never used to leak, now about a drop a night and getting worse. Should have left it alone. will likely replace again and see what happens. No small task.

Chris
89 Carrera

Mine does not leak at all when sitting? Only after a drive a bit.
I know what you mean about 'leave well enough alone' but either way it is a crap shoot..if this is the original seal it is 38 years old....Liquimolly makes a 'seal refresher' added to the oil but what are the downsides to that....over expansion...too soft after...no idea but putting an additive in my oil never appealed to me.