I have an ongoing problem with my outboard. It has Magnapower ignition. The electrical has all checked out ok, and all the fuel lines, primer bulb has been replaced, as well as the lines that "power" the fuel pump. The tank has been cleaned and the fuel pump and carb rebuilt. I still have a fuel "starvation" problem that causes a backfire/missing problem. The primer bulb gets very soft after running a while, and fuel barely dribbles into the fuel filter. Acts like an air leak.......any suggestions on where to look?