A thought has crossed my mind (not a long journey!!).
My RP fuel pump sometimes sticks with the priming lever in the "up" position - so the engine stops once the carb empties. Also I was once told - but don't necessary believe it - that it is possble to install the fuel pump with the lever on the "wrong" side of the cam shaft.
Take the carb bowl off, turn the engine over a few times and ensure fuel gushes from the needle valve.
My RP fuel pump sometimes sticks with the priming lever in the "up" position - so the engine stops once the carb empties. Also I was once told - but don't necessary believe it - that it is possble to install the fuel pump with the lever on the "wrong" side of the cam shaft.
Take the carb bowl off, turn the engine over a few times and ensure fuel gushes from the needle valve.
Rick
In deepest Norfolk
In deepest Norfolk