Exhaust manifold leak

[Aspen500]

Don't think I've ever done brazing on cast iron. The most I did was electric arc WAAAAAAAAAAAAAAAAAAAAAAY back in a high school metals class, about 40 years ago. I recall beveling the crack or broken piece, cleaning with a stainless brush and preheating. If it was a crack, drilling a small hole at each end to prevent the crack from migrating further and THEN preheating. Weld it up using high nickle content electrodes and then let it cool slowly back to room temp. I'm sure there was more to it than that but as I said, it's been 40 years.

 

[Ele115]

Thanks guys,
The plugs that are in the head are flush and are still in there. They never leaked when I ran headers. I was hoping that a gasket or either the red or copper RTV would resolve the issue without having to find Non AIR manifolds. I will pull the manifolds off again and check to make sure they're flat. Would there be any reason to run a gasket instead of using RTV other than sealing issues? or the other way around?

The header flange covered that little hole. You're in a spot. Now that you dont run headers you have the openings