FUEL SWITCH
When the engine has started, a negative pressure(vacuum) is generated at the
intake port. The negative pressure acts upon the diaphragm of the fuel switch and ti
pressed down the spring which supports the diaphragm so that the fuel passageway is
opened and fuel is fed to the carburetor.
When the engine has stopped, the spring presses the valve, the fuel
passagewayos closed, and no fuel flows to the engine.
Fuel switch