Don't get stuck on the side of the road! This 1950-1952 Fuel Reserve Petcock Tap is used when your VW's fuel tank had no provisions for a fuel tank level sending unit and retains a gallon or so of fuel in the tank in case of an emergency. The pipe comes out of the bottom of the fuel tank and is designed to prevent fuel from being drawn off the bottom of the tank and to keep rust, rocks, and other debris from plugging the pipe.
Under normal conditions, the tap will be set in the vertical position. If the engine begins to sputter due to lack of fuel, just turn the tap 90 degrees to access the fuel reserve that will provide roughly a gallon of fuel. It is very important to return the tap to the vertical position when refueling to ensure a full tank. If the tap is turned to a 45 degree position, the fuel supply will be shut off.
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