Oil Leak

I had a large amount of oil leaking from the back of my freshly re-built 225 V6 (1968) where the block and the intake manifold meet. I am using an aluminum Offenhauser intake. I took it apart and re sealed it using black rtv. I put it back together and it is leaking just as bad as before. I have oil dye in the oil and I can see it is leaking from the middle of the intake, and it is a large amount, I wouldn't be worried about a small seep. I am using breathers on the valve covers. Could there be a problem with too much pressure in the block? Should I use the rubber seals instead of the RTV? Has anyone ran into this problem?

 

Sounds to me like he means the back of the intake, at the center.

On the AMC engines, there are rubber seals that go across the valley, and seal the ends of the manifold. Those seals tend to squirt out, esp. when they are lubed up with silicone. Some folks leave them out, and depend on a bead of silicone for the seal. Others glue them to the block with gasket cement or weatherstrip cement to prevent them from moving during assembly.

 

yep, oil is leaking from intake between the manifold and the block at the back, cant get a camera in there. I used oil dye so it is very easy to see where it is coming from. This is a Buick 225 V6. I was just wondering if it is common for this to happen and if maybe too much case pressure was blowing out the silicone. I think I might try gluing the seals in next time. Any more ideas?