Fuel Tank Shutoff Valve
The fuel tank shutoff valve is located in fuel tank(s). See Fig 1. When ignition switch is in OFF position, fuel tank shutoff valves are closed and fuel in the tanks is isolated. During refueling, fuel tank shutoff valve acts as a check valve and allows flow due to pressure differential between fuel being added from fill station and fuel in the tank.
The fuel tank shutoff valve internal solenoid valves also have capability of being manually locked down. While servicing vehicle, if it becomes necessary to remove the fuel tank, lock down feature provides an added measure of safety.
The fuel tank shutoff valve has an internal Canadian Gas Association (CGA) type 9 fusible link pressure relief device that senses internal fuel tank gas temperature. Fuel tank is vented to the atmosphere when internal fuel tank gas temperature reaches 217°F (199°C) and melts fusible link. The escaping gas is vented through a vent line.