have 06 yamaha 40hp. Had carbs pulled and sonic cleaned and adjusted. Went out with half tank of fuel boat would not run over 1100 rpm. Thought maybe condenstation. filled tank (24 gal) and added isopropl alchohol. Took boat out and ran fine throught rpm range except 2200-3000, wanted to stall, could throttle through it. only happens under load can not duplicate on land.
