Blown head gasket on my 08 moomba xlx

[Brandoncyruss]

Hey Guys. I might have lucked out. The guy i bought the boat from is splitting everything with me. The mechanic changed the oil and ran it for 30 minutes... seemed to look fine. Good compression. No milky oil. Planning on taking it to the river and running it and monitoring the oil.
Appreciate all the input fellas.

[beat taco]

Hey Guys. I might have lucked out. The guy i bought the boat from is splitting everything with me. The mechanic changed the oil and ran it for 30 minutes... seemed to look fine. Good compression. No milky oil. Planning on taking it to the river and running it and monitoring the oil.
Appreciate all the input fellas.

My very extensive experience with bad head gaskets is that they can sometimes fool a compression test since they build pressure over repeated revolutions. They always fail a leak down test. So if a mechanic ever says you have a bad head gasket, the very next step anyone should take is to confirm the condition of your engine with a leak down test if that was not the method the mechanic used to diagnose the gasket. This eliminates any guess work. Some failures are obvious while others are not. Looks like you most likely got a bad diagnosis in the beginning, congrats. I just wanted to clarify what I was saying in my post above for anyone who may need to diagnose a problem like this that is reading along.

[Fastest1]

Water in the oil is pretty common in boats. Especially if they have been sitting. Its as much condensation as anything else.

The fact that operating temperature is pretty low too. In an automotive application oil temperature is right around 230f. Water boils off during the normal operation. Many times boats run much cooler never vaporizing the moisture in the crankcase. I believe this is one of the leading causes of short engine life in boat applications.