Early in my boating
time a marine
pro taught me a trick with gas powered outboards. Install a shut off valve in the fuel
line and use that to stop the motor
instead of the engine
mounted "shut off", same as you'd do with cabin
stove when using solenoid to shut it off instead of the stove knobs. This way there is no left over gas in the carb.
As an added bonus this shut off valve, if put in a discrete place, works as an anti-theft device.