Crazy Behavior -- 1999 90HP 2-stroke

[Pete532]

After running fine for years, just started experiencing this repeatable behavior:

Start from cold, idle for about 2 minutes, then cruise at about 3700 RPM. After 0.5 miles, engine dies completely. It restarts OK, but will only respond to a very small amount of throttle. I can continue underway at just above idle speed. After about 5 minutes, it starts to recover, and engine speed gradually increases. After about 10 minutes, I can resume cruising at 3700 RPM, at which time it runs perfectly for the rest of my regular 4 mile trip.

Based on experience to date, this does NOT happen if the boat was used up to 6 hours earlier. It DOES happen if the boat has been unused for 2 days or more.

Oil and temp indicators look good.

Any suggestions greatly appreciated.

Thanks

[robert graham]

My motor is a 1999 2 stroke also, and I would check your fuel delivery system starting at the tank pick-up, fuel tank vent, tank fittings, primer bulb, fuel quick-disconnect on cowling, fuel filter and fuel pump. Sounds like maybe bad O-ring, seal, gasket or air in-leakage to fuel system. Good luck and let us know what you find!

[Pete532]

Robert: Thanks for the great tips. I'll let you know what transpires.