Misfueling Protection

A mechanical system has been developed in order to help prevent a mis-fueling situation. To make sure that the diesel vehicles are only refueled with the proper diesel fuel, a mechanical flap has been added to the fuel filler neck.

Fig 1: Identifying Fuel Filler Neck

Courtesy of BMW OF NORTH AMERICA, INC.

As the following illustrations show, only a fuel nozzle with a diameter of approximately 24 mm can fit. If the diameter is approximately 21 mm, the flap (4) does not open as the hinged lever (7) and the locking lever (2) cannot be pushed apart.

If a diesel fuel nozzle is inserted, this pushes the locking lever (2) and the hinged lever (7) at the same time. The hinged lever is pushed outwards against the tension spring (3) and releases the flap (4). This is only possible, however, if the hinged lever cannot move freely and is also locked in position by the fuel nozzle.

To open the protection against incorrect refuelling feature in the workshop, a special tool is required.

Fig 2: Identifying Fuel Nozzle

Courtesy of BMW OF NORTH AMERICA, INC.