Rear Main Seal leak

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SuperStock426

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Fired up my 440 on Monday. Everything sounded good, good oil pressure, no over heating issues. Ran it for 20 minutes at 2000 rpm's to break in the cam. Then alas I look under the car and see a puddle of oil. Put it on the lift and wouldn't you know it, the rear main seal was leaking. When I built this engine I installed the "red" high performance rear main seal from Fel-Pro. Everything was done correctly except I didn't stagger the rear main seal. The engine was built in 2014 and fired it up this past Monday. Is it possible after sitting for nearly 7 years on an engine stand that the rear seal could have dried out? I ordered a new red seal along with a stock type rubber one to get the side seals as the red one doesn't come with side seals. I dropped the drag link and the oil pan, pulled out the main seal bridge and the rear main cap. Cleaned everything thoroughly and re- installed it with the stock type seal except this time I staggered it. Hopefully it'll seal up this time. Has anyone else had this issue?
 
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always stagger. Just makes sense on these split rear main seals.
 
Is this a BB? If so it may be one of two problems. Maybe the seal was installed backwards, or the rear main seal cap may have had the bottom of the bolt hole knocked out by using to long of bolts. Like this one pictured.

C473A10D-8AC4-482F-9D51-8188409FCD59.jpeg
 
Is this a BB? If so it may be one of two problems. Maybe the seal was installed backwards, or the rear main seal cap may have had the bottom of the bolt hole knocked out by using to long of bolts. Like this one pictured.

View attachment 1715698567
Yes. It's a 440. Seal was installed correctly. I double checked it . The seal bridge looked fine.
 
Remove the two pan bolts in that seal cap and use a ice pick or something like it and see if the bolt holes have a bottom.
 
Remove the two pan bolts in that seal cap and use a ice pick or something like it and see if the bolt holes have a bottom.
I removed it today when I cleaned it up and reinstalled it with a new staggered seal. I closely inspected it when I cleaned it up and everything looked good. The oil pan is still off of the engine so I'll double check the bolt holes.
 
I had the Viton rubber with the billet cap available from Mancini Racing, twice on my 383...
Still leaks.
 
Did you inspect the knurling on the crankshaft where the seal rides? If the knurling grooves are worn its always going to leak.
 
and if its a reverse rotating boat motor crank, the wick lines are the wrong direction......Now that would be a WTF moment!
 
One piece with a flange is not possible.

yes there is , about $75 or so , you have to split it w/ a razor blade to install it . but it will only have one seam in it , which u put up in the block around a 12 o`clock position ------
My rear main seal housing was cast and drilled offset , I fitted it up to the block all cleaned up and w/ no side seals , just the cranl seal in it , it set off to one side . Bought an aftermarket billet one .
 
yes there is , about $75 or so , you have to split it w/ a razor blade to install it . but it will only have one seam in it , which u put up in the block around a 12 o`clock position ------
My rear main seal housing was cast and drilled offset , I fitted it up to the block all cleaned up and w/ no side seals , just the cranl seal in it , it set off to one side . Bought an aftermarket billet one .
Well then like I said with a flange, it is impossible to install a ONE piece seal! If you have to cut it, it is not a one piece seal.
 
Well then like I said with a flange, it is impossible to install a ONE piece seal! If you have to cut it, it is not a one piece seal.

SURE IT IS , ALL ONE PIECE , U DONT SEPARATE IT !----LOL
I KINDA LIKE THE IDEA, BUT NOT $75 WORTH .
 
Didn't I hear of an egine builder that bored a recess in the rear cap assembly, then it was able to accept a 1 piece GM seal?
 
Look at your crank right behind your flywheel or flex plate, and tell me how you can adapt a Chubby or any other one piece seal?
 
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