5. FUEL SYSTEM MOVIE SYSTEM AUTO FUEL VALVE No Smoking! First clean the fuel tube. Disconnect the fuel tube and vacuum tube from the carburetor. Connect a vacuum pump to the vacuum tube and apply vacuum. Check if fuel flows out. Auto Fuel Valve · The valve is operating normally if fuel flows out of the fuel tube when the vacuum is applied. · The fuel shall stop flowing out when the vacuum pump is disconnected. If the fuel valve does not operate normally, Check the vacuum diaphragm for poor installation or damage and inspect the fuel tube for clogging. FUEL UNIT Fuel Unit Refer to Section 17 for the fuel unit inspection. REMOVAL Disconnect the fuel unit wire connector. Turn the fuel unit retainer counterclockwise and remove the fuel unit. Do not bend the fuel unit float arm; otherwise, the fuel unit metering values will be incorrect. Mark INSTALLATION Inspect the fuel unit gasket for damage. Install the fuel unit by aligning the groove in the fuel unit with the tab on the fuel tank. Retainer 5-11