Originally Posted by Phil_F_NM

The breather issue could be partially solved by capping the connection at the intake manifold and letting the breather drain into a can filled with steel wool, just to keep things clean. If the black smoke disappears, you have a winner and will need to suss out why there is that much oil vapor pushing out the top end. If you just have stuck rings, they can be freed up. If it's really worn out, you could put some heavier oil or engine restore in there to see if you can bump up the compression a bit.

Does the oil cap blast off forcefully when the motor is running or just dance around?

Phil Forrest