I found this for sale. Did someone just put the rings in upside down? Bad cylinder? Leaking oil? Crack in the block. Might be worth looking at. Are these engines even any good?$180
Was just rebuilt 10k miles ago. Issues with one of the cylinders. When we pulled it, it still ran. It was leaking oil. My mechanic said one of the cylinders went bad, but couldn’t say how bad without breaking it down. That’s all we know. It came out of a ‘79 mustang.