Gas tank is vented. I had a clear filter in front of carburetor and I could see there was no liquid gas in line. I turned on electric fuel pump and it filled fuel filter bulb. Started right up. Farther down road with electric pump running same issue and would not start. I tried removing filter and even though engine and pump was off and no visible fuel, it was under high pressure when I started loosing filter connection. I installed a heat shield this morning and fuel line insulation tomorrow and then try it again.