[capnward]

Hi Flathead Lake Sailor, with a Flathead engine,

Since your engine runs fine once it starts, there's probably not much water in the gas, or crud restricting the fuel line or carburetor orifices/jets, or a problem with the fuel pump. Although, I have a mechanical pump, so I don't know about OPSS. I suspect the timing, or the fuel/air mixture being too lean, or the choke adjustment as the likely culprits. Having a fuel pressure gauge in the line just before the carb could tell you if you have a leak in the fuel line, if the needle drops after the line is pressurized. That and wet hoses. (Shudder) Be vigilant! Always sniff for gas. Good Luck.