Rear Main Seal

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Mango

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Have you used Bars Rear Main Seal Product to stop rear main seal leaks

I though I had a small leak that grew after replacing intake manifold gaskets!

The oil leak is getting worse now blowing under the truck to the rear axel spotty and more oil on the ground
I am convinced its the rear main or a cracked block?

Oil sending unit is dry valve covers dry Intake maybe a small leak
 

sickchev

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Did you remember your gasket on the distributor?
 

squaredeal91

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Only experience on it I have is once recommended it to a friend with an 88 t bird 3.8l leaking oil like it was free. Bout a quart a day for 10 mile commute. I told her how big a deal rear main is and she asked of there was anything else. I said you can try an oil stop leak and it actually stopped the oil leak.
On another note/ story, this was when delo changed and went ck4 on me red cap gerrrr. I changed oil in a 1990 caprice with delo 15w40 like normal. Same day it started leaking oil bad. Rechanged oil to valvoline and it stopped leaking. I haven't bought red cap delo ever since.
 

squaredeal91

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What year are you? The 2 piece rear main seal ain't too bad on a square.
 

SquareRoot

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Have you used Bars Rear Main Seal Product to stop rear main seal leaks

I though I had a small leak that grew after replacing intake manifold gaskets!

The oil leak is getting worse now blowing under the truck to the rear axel spotty and more oil on the ground
I am convinced its the rear main or a cracked block?

Oil sending unit is dry valve covers dry Intake maybe a small leak
@mtbadbob Got another one!
 

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newguy11

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Leaking from rear rail of the intake?
If the leak got worse after he changed the intake I think that’s a big red flag. The front and rear rail on the sbc intake is notorious for leaking.
Although, he’d have a nasty vacuum leak too and I think he would’ve mentioned that
 

squaredeal91

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My dad always told me, that if you use any type of "stop leak" what else is it going to plug up?
Maybe im wrong, but The oil stop leak doesn't work like radiator stop leaks. It's a chemical that the rubber reacts too and it tightens up and stops the leak is how I understand it.
 

gmbellew

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I did have a rear main seal leak once and Bars rear main seal repair did help slow it substantially before it was replaced. but I think OPs sudden increase in oil leaking is more likely a result of the recent intake manifold RnR. or at least that's the best guess until he tracks it down. I wouldn't dump in any sealer additives unless I had it narrowed down to the rear main seal.
 

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