Did you check the inlet check valve ? It is usually the flat red rubber type in the bottom of the carb under the pump. I only ask because to me when you have the pump discharge ball or weight in the circuit it will drop as soon as the pump stops to keep fuel right there and then the inlet check valve should open and let fuel in the circuit to keep a full and ready pump shot. Then of course the invlet valve should seat and seal so it has a full shot of fuel in the pump circuit. Ron
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