I have the above described engine that is difficult to start after having run long enough to reach full operating temp. then stopped for a short time and then attempted to start again. If the engine dies after having run at low speeds it's a real bear to re-start. I've tried combinations of throttle feed and choke but nothing seems to help. Could tweeking the points (all ignition parts and spark plugs have been replaced using OEM parts) help this problem? Carb has been completly disassembled and cleaned and the fuel pump has been re-built. All new fuel lines are in place.