Yes, Terry.

In an HB .40 engine. The crankshaft has a crescent shaped counter-weight and it broke between the crank-pin and the gas passage. The con-rod was bent also,

I also saw numerous OS FX engines that had broken the crankshaft at the shaft valve opening (below the carburettor), because of the same reasons.

Some people are too ignorant to check whether their engine can turn over. They don't bother to prime it properly, and simply "wack" it with the starter.

A hydraulic lock is a solid, incompressible resistance. And when coupled with a reasonably strong starter (Sullivan?), the result is a catastrophic crankshaft breakage, and/or twisted rod, and/or perforated piston, and/or broken wrist-pin.

Some modelers are their own engine's worst enemy.