This doe's not concern what I would call a Performance boat, I'm just trying to help a freind. 2008 Volvo Penta 496 with raw water cooling, cast manifolds and thru prop exhaust. The owner forgot to put the cap back on the flush port, took the boat out for a spin and within five minutes the engine over-heated. The pick-up pump was most likely sucking air thru the flush port. After the temp went down, He tried to restart the engine to find it would not turn over and the breaker would kick out. The boat gets towed in. As it turns out, the pistons were hydro-locking! Water in the cylinders on both sides and milk shake for oil! What the hell happend? We can't figure out how water got in both cylinder banks and how did water get in the oil as well? I told my buddy, the first thing I would do would be a compression test then take it from there.
Does anyone out there have a clue as to what might have happend. How could this all be linked together? Thanks for the help!