Still, this repair worked. While this serves as proof of the feasibility of repairing an engine block with JB Weld, there is one ultimate test of JB Weld epoxy: build an engine out of it.

A machinist fixes a massive crack in an old cast iron engine block with a drill, a handful of bolts, and a tube of red loc-tite.

Sadly, poor — the rod disintegrates in mere seconds, completely unable to hold together despite the JB Weld’s best efforts. It’s a fantastic material, yes – but it can’t do everything.