Fuel Filler Check Valve
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The fuel filler check valve prevents the escape of fuel through the fuel filler pipe if the vehicle overturns. The fuel filler check valve is installed in a stub pipe in the rear right corner of the fuel tank and sealed with an O-ring seal.
A door on the fuel filler check valve is normally held closed by a spring. During filling, the weight of fuel in the fuel filler pipe is sufficient to open the door and allow fuel into the fuel tank.