Loose fuel cap.

[Bisley45LC]

When I put my Sea Ray w/Mercruiser 5.0 Alpha in the water it wouldn't start. Never a problem before. I found the gas cap loose and was wondering if that could cause a problem. In the driveway the ignition system checked OK, and had fuel to the carburetor but was not getting fuel out the jets. Sprayed fuel into the engine and it ran a short time and stopped. I tapped gently on the side of the carburetor and after a few tries it fired and runs fine. Figured the float was hung up. Hate to have this happen away from shore.

 

[chiefalen]

You removed the fuel line from the fitting that enters the carb? There is a fuel filter in there.

You crank the motor and have fuel coming out of the line?

If yes rebuild the carb, if the filter was clean if dirty the filter then that might be your problem.