At the end of the season, I took my boat out for a final run, which was about 45 minutes @4500 rpm. When I returned to the dock at idle speed for about 10 minutes the motor quit and would not restart. Had fuel and spark but there was salt water in the cylinders when I pulled the plugs. Someone suggested that I had blown a head gasket, but with having a closed cooling system on the motor side I felt it should have been anti-freeze and not salt water in the cylinders. Now I am ready to attack the problem for this season, so I installed a new battery and fuel filter. Turns over fine but still won't start. The one thing I did notice was that the timing belt seems to be very worn and possibly slipped timing. Does this make sense, that the motor would have just quit like that and if so how hard is it to replace the timing belt. How did the salt water get into the cylinders? Any help would be appriciated.
