The engine is not cowled. I connect the carb line to the fuel can and put air pressure in the vent line for defueling. Fuel goes back into the can as though the engine is using the fuel.

To shut off the pressure line is disconnected. I also use an overflow catcher on the vent line when fueling.

Originally I tried to use each pump but they were all clumsy in operation. Air pressure was a remedy of last resort that worked better than the pumps.

Bill