Since there is an engine knock thread going, I thought I would share.

Ive had 2 engines cone in with holes in them. One had a hole in the pan and would not start, the other had what the owner said started as a mild knock from low oil which turned into a major knock. It was still running before o broke it down, although loud and rough.

The first I elected to scrap without breaking down. The second I broke down and found a hole in the side of the block once I removed the motor mount bracket. 2 broken rods, one piston had been hammered by the valves.

 

Wow, that is carnage. I expect that's something what my old engine looked like. Safe to say that these failures are caused by low oil? The only other option in my case was hydro locking due to oil ingestion in the combustion chamber.