Stalling after initial startup

Bought used 1999 boat with 150 Johnson outboard. When we did test drive with previous owner everything went fine. In a subsequent fishing trip, engine kept dying when trolling. When trying to restart, it would start up but would die when given more than marginal throttle...limped, sputtered back to shore. When asking around regards to problem, everyone seemed to agree the motor was running rich, not built for trolling, etc....So, took kids tubing, no problem. Next time we took the boat out to do some waterskiing, we got one kid around, but when we tried to start up on the second round, had the same engine problem as when trolling. Stranded in the middle of the lake, and once again, engine would start, but could not add throttle, engine would move forward, then die, over and over till we got to shore! HELP!! Fuel pump, bulb,???

Re: Stalling after initial startup

check your compression, spark, but sounds like dirty carbs.

Re: Stalling after initial startup

You should be able to idle that motor in gear all day long. Like Tashasdaddy said, start at the top with compression and spark tests and work your way down. Sounds like carb to me too, but this could just as easily be bad wires, weak grounds, blown head gasket etc. You need to eliminate those possibilities first.

Re: Stalling after initial startup

As both above have said, you should be able to idle this motor for extended periods without problems. After the compression test tells you the motor is not beat, then you should be able to get it running right without spending a ton of money.