oil leaking from (rear main seal)??? worth replacing??
 

hey guys. what i have is a 396 big block. I bought the engine last year from a budy who had it rebuily and lost interest in it. So anywho. I ran the engine in my 72 k5 for about 6 months only drove the thing about once a week and for about an hour, noticed every time it was parked that a small leak would start from the rear of the oil pan. Just figured it was the oil pan gasket. I pulled the engine and replaced the gasket taking extra care to make sure it was done correct. To make a long story short, its still leaking! nothing too crazy but maybe a drop or two in idle (assuming more in higher RPMs). So now i'm prety sure its the rear main seal thats doing the leaking. My question is, is this seal worth replacing? i've heard that BBC rear main seals are notorious for leaking period, i'm at the point that the truck isnt all puit back together from the first tear down so right now would be the time to pull the engine, just want to know if its even worth re-sealing the main seal???? any opionions or comments would be greatly appreciated, thank you.

Re: oil leaking from (rear main seal)??? worth replacing??
 

I'm my opinion, if it's a fresh quality rebuild then yes it's worth I to fix the leak. Most rear main leaks turn out to be intake, valve cover, oil sender, ect leaks. I'd clean it off real good and find the leak, you may luck out with a fresh set of valve cover gaskets.
Posted via Mobile Device

Re: oil leaking from (rear main seal)??? worth replacing??
 

Investigate all the possibilities of leaks on top of the engine like Lee H said. Many a "rear main" oil leak was actually coming from the top of the engine.

Gary

Re: oil leaking from (rear main seal)??? worth replacing??
 

Hey guys thanks for he input....I looked all over for a possible valve cover, intake manifold, oil sender leak and found nothing. So I pulled the engine out, yanked the fly wheel off and took a look at the main seal and it does appear to be leaking from there, the two freeze plugs in the back seem a little oily, is it possible that the freeze plugs are leaking?
Posted via Mobile Device

Re: oil leaking from (rear main seal)??? worth replacing??
 

oil gallery plugs ? i would change every plug back there now ,its cheap to do ,also change the rear main as well ,

Re: oil leaking from (rear main seal)??? worth replacing??
 

While you have it apart put the pan back on without any gaskets. See how it sits along the sides and the gap around the curve on the back. I had one that was warped and kept squeezing out the rear rubber gasket making it leak.
Slip a flashlight inside first so the light shows thru the gap. A little hammer work will cure it. Or a big hammer and chunk of pipe. LOL!!!