by David Anderson
(New Concord, OH, USA)
Engine runs perfect below half throttle. Idles fine and runs fine until you want to get up on top of the water. Then, under full throttle, it will start to surge, backfire, surge, backfire etc. Pull the throttle back to about half throttle and it runs fine. Feels like it's running out of fuel at that point. Thinking there's a restriction somewhere in the fuel supply system. David