[sastanley]

The water incursion happens from an extended crank/no start episode. The impeller in the raw water pump spins with the starter, pushes water thru the engine and out the exhaust pipe at the mixer..since the engine is not running to expel the water from the water lift muffler, it fills up and backs into the hot exhaust section..If the previous owner did not immediately get the water out of the cylinders/crankcase and get the engine running you end up with a frozen engine like you are likely dealing with.

The "fix" is to close the raw water intake valve until the engine is running. But, once it is running move as quickly down to the valve as you can so you don't burn up the impeller from running it dry.

If you get the engine tuned correctly so that it starts fairly quickly (5-10 seconds) you usually don't have to worry about water incursion from cranking. I typically leave my valve closed after the engine has been sitting a long time..she tends to take a little longer on the cranking after a long sit.