One piston has a rather large hole in the top. Perfect compression in the other 7 and good oil pressure. Classic lean-burn failure for a turbocharged gas engine, probably caused by low fuel pressure or crap in the carb.Don't remember.... what was wrong with the failed one?
So now we've got spare parts for the pair in the boat...out the ole wazoo... And I'm installing pyrometers in the exhaust of both engines.