Engine runs great cold, I can run it wide open, or troll around for about half an hour. After about that much time if I try to bring it down it stalls, it'll restart if i hold the throttle 3/4 full, I can rev it up,but as soon as i bring the throttle back to put it in gear, it stumbles and stalls. Carb has been recently rebuilt, choke is set, fuel - water seperator installed, electronic ignition installed, new plugs ( 3 times). Eventually it will restart and I can get to shore, any thoughts?