1998 150hp problem

[Scott1967]

I have a 1998 150hp ocean runner. When I start the motor it will idle then advance to 2500-3000 rpm. The motor will stay at 3000rpm for 30 seconds or so then idle down and stall. The motor sounds ruff when advancing up and comming down. Good compression, good spark. Any suggestions?

[gasman]

possible fuel restricion see if primer ball is going flat

[ppirce]

Definitely a fuel flow problem. If the gas hose is old, I have seen varnish come loose from the side of the hose and block it. The other most common is a stuck float in the carb. The motor will burn the fuel in the carb. bowl but the float will not sink and allow enough fuel into the bowl to continue running. I have seen floats where the pin the float rotates on is made out of steel and the part connected to the float is made of brass. The steel part rusts and will not allow the float to rotate freely. This will cause exactly the symptoms you describe.