I have a mid 70's 455 block with Edelbrock aluminum heads which seems to be leaking oil from the head gaskets. The intake and valve covers are dry. All 4 corners of the block are wet with the rear passenger side leaking the worst. The motor has about 2000 miles on it since rebuilt. Planning on removing the heads to investigate. Any ideas on why this is happening?
thanks

 

Before you take it apart check your intake manifold in the rear. Also you can try retorquing your head bolts, clean it up really well and monitor for a short while.

 

Thanks for the reply, I recently re torqued the head bolts and got some movement on most of them. My thought is that maybe oil from the drain holes got between the block and head and possibly affected the gasket? I also had the intake off thinking it had to be coming from one of the rear corners, unfortunately it was not. The leaks do not amount to much on 3 of the 4 corners, the rear passenger side will leak enough to blow back on the transmission in under 5 miles.

 

The only way heads can leak oil is if there is serious casting flaws! There is no pressurized oil, the only oil that is technically flowing thru the head is from the oil drain back holes.

If you see oil leaking around the head gasket, it’s almost certainly coming from the corner of the intake meets the block and heads. It’s common practice to discard the rubber end seals and use a need of quality RTV instead. Dry fit the manifold (with the gasket) to get an idea of how thick a bead of sealer you need. And though some people say it’s not needed, retorque the bolts after a few heat cycles. Good luck

 

Not knowing a lot of the specifics that went into this motor, I am wondering if maybe the wrong head gaskets were used. Edelbrock lists a specific part number to use with their aluminum heads. I suppose the the gasket may not be lined up perfectly between the head and block causing the leak at the drain hole.

 

You have had two people give you advise as to the issue and you have not heard them.
It is most likely in intake gasket corners not head gaskets.
Re read.