Once the engine is running, it is generally ok. The problem is it usually takes 3 pulls on the handle (aircooled) before it actually fires. New spark plugs in recently and the carb is clean and tidy, just did it myself with new gaskets, etc.
With the engine off, would the fuel just run back down the line? I'm thinking that a non-return valve after the pump and before the carb might solve this. Or should I look at replacing the pump itself?
Thanks