I've been having some fuel delivery problems lately. Replaced the filter in the tank and tubing. My rubber priming bulb ends up flat after running at 60% rpm's for about 20 minutes. The engine slows down and will stop. Wait until the rubber bulb gets round again and it will again work....until the bulb gets flat again. Any suggestions? Most of the archived question/answers don't quite hit my problem on the nose. I always thought a flat bulb meant a problem on the uptake side before the rubber bulb toward the fuel tank. Like a plugged filter or broken off piece of tubing. Hope somebody can simplify this problem with an answer. These things are vexingly easy at times, just not on my machine! thanks, all Mike