schlackoff, you have had too many hard drugs too long.

Sounds like a cracked crankcase. Can come from a connecting rod
parting company with piston or crank. Invariably expensive.

I have never seen a case like that where the engine continued to run. Why
do
you think that is the case?

Most of the time I've see that happen, the engine does continue to run
on the cylinders it has left operating. At least until it doesn't have
any more oil. I've seen engines continue to run (very poorly) in
everything from a 2 cyl lawnmower where the broken rod punched a nickle
sized hole in the crankcase to drag racers, where it happens frequently.

Steve