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Main Bearing Seal Leaking

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Jman

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I recently had the engine rebuilt in my '66 AH sprite, and the main bearing seal is leaking like crazy. I did a search to see if there was anyone else having problems w/ the cork seals but came up empty. Is there a secret to installing them so they dont leak? Any suggestions would be greatly appreciated.

Thanks
Jman
 
Only leaks when the engine is running, basically pours out. My mechanic said that he was pretty sure he had installed them right, but he asked me to find out if there was a proven process.
 
Front and rear both? Oh yea and it is a 1275 I think.

Is it really leaking from the front and back of the oil pan or just where?

If pan he did not install the cork gaskets front and rear properly.
 
There is no main bearing seal on an A Series engine. There is a scroll cut on the crank that is supposed to "wind" the oil back into the engine. If the mechanic disturbed the scroll cover on the rear of the block, and didn't get it re-set properly, there can be a massive leak while running.
You may just have an oil pan leak.
Jack, a '66 should have a "big crank" 1098 in it.
Jeff
 
Bugeye58 said:
There is no main bearing seal on an A Series engine. There is a scroll cut on the crank that is supposed to "wind" the oil back into the engine. If the mechanic disturbed the scroll cover on the rear of the block, and didn't get it re-set properly, there can be a massive leak while running.
You may just have an oil pan leak.
Jack, a '66 should have a "big crank" 1098 in it.
Jeff
Click to expand...
I was going to break it to him slowly. The threaded dealy that winds the oil works good when running, but not so good when its stopped and oil runs down. Sounds like he has worse problems. Hopefully its just the pan gaskets, just drop it and fix, otherwise the motor will have to come out or at least be raised for that front seal. There is a front main rubber lip seal.
 
Yea, I was kinda working up to that as well.

I for some reason can not remember what engines go with what years, need to write it down.
 
Jack:
948: 1958 ~ 1962
1098:
Small crank, 1963 ~ 1964
Big crank, 1965 ~ 1966
1275: 1967 ~ 1974
1500: 1975 ~ End of Production.
Jeff
 
No matter what year/displacement he needs to remove the oil filler cap (cover the hole with a clean rag and a couple of rubber bands) and see if the oil leakage suddenly slows down, if it does I think that there may be a PCV question. I've seen it too many times.
Bill
 
Ok Jeff, printed that and will post it, hehe. Thanks.
 
Alot of good advice here, I'll add something to the frey, when getting a bottom end gasket set for a 1275, get the better Payen set with the rubber pan rail end gaskets in it, they do a much better job than the cork. Also mentioned here is venting the crankcase. IF your problem keeps getting worse it could be that the rings are not seating.
 
Thanks Fellas, It's a 1098. The front isnt leaking. Its the rear main seal, I'm pretty sure its not the pan seal. I'll have to look and see what you are talking about with the scroll deal. At least now I have some info to take to him on monday. I took him the engine in pieces in a wash tub, and he had never messed w/ an AH before, so we kinda just winged it. I guess it could be worse!

Thanks

Jman
 
Is a link someplace on building a no leaker, not sure if that applies however. He did have some preaty detailed instructions on the scroll seal cover thing.
 
Sure it is, glad you guys have better memories than I.
 
Think the 66 took engine oil in the transmission as well.
 
Hey guys, I hate to bump a thread that's this old but I finally had a chance to work on my sprite again and removed the seal that my mechanic had put in. Worked like a charm. No more leaks and the engine runs great. Thanks for the great advice.
 
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