Fuel Pump: Service and Repair

Fuel pump

WARNING:
Removing the fuel pump involves partial dismantling of the car's fuel system. The following points must therefore be observed in connection with the work:
- Work only in a well-ventilated area If approved equipment for the extraction of fuel vapors is available, be sure to use it.
- Wear suitable gloves. Prolonged contact with fuel can cause skin irritation or dermatitis.
- Keep a class BE fire extinguisher near at hand. Be mindful of the danger of sparks caused by short circuits and when connecting and disconnecting leads in electrical circuits.
- No smoking anywhere in the vicinity.
- Wear protective goggles.

Dismantling

IMPORTANT:
- The car should be parked on a level surface. If the tank is full and the car is jacked up at the rear when the pump is removed, it is very likely that fuel will run out.
- Place protective paper over the carpeting when the pump is removed as there is a risk of fuel spilling out.

1. Raise the rear seat cushions and fold the carpeting out of the way.







2. Remove the fuel pump cover.
3. Unplug the upper connector.

IMPORTANT: The connector on the pump must not be removed.

4. Carefully work loose the check valves with fuel lines from the pump (move the yellow hooks to one side with a screwdriver). The check valves are connected to the pump with quick-release couplings. The white ones are the delivery side and marked "Pressure" on the pump. The black ones are the return side and are marked "Return" on the pump. Move them out of the way and secure them under the plate seam.







5. Remove the screw ring using the 83 94 462 Fuel pump tool.







6. Lift up the pump until the top is approximately 50 mm above the fuel tank. Turn the pump clockwise approximately 80 degree and remove it carefully. Have a cloth or paper ready to collect any fuel that spills out.







7. Transfer the pump to a suitable receptacle and pour off the fuel.

To fit







NOTE: Spray the connectors with Kontakt 61, part no. 30 04 520, before connecting them.

1. Clean sealing surfaces.
2. Fit a new O-ring in the tank groove.
3. Carefully lower the pump into its correct position, making sure that the alignment marks on the tank and fuel pump are opposite one other. Carefully press the pump downward into position.







IMPORTANT: It is essential to the fuel level sensor function that the pump unit be positioned correctly.

4. Lubricate the screw threads on the pump cover and the upper edge of the pump with acid-free vaseline to prevent the pump from turning when the screw ring is tightened.
5. Attach the screw ring with the 83 94 462 Fuel pump tool.

Tightening torque: 75 Nm (55 ft. lbs.)

6. Inspect and lubricate the O-rings on the fuel line connections with acid-free vaseline. Connect the fuel line connections to the pump.







7. Make sure that the yellow hooks have snapped in place over the connections.
8. Plug in the connector.
9. Check that the pump functions properly and that it does not leak.
10. Fit the fuel pump cover, replace the rear seat cushions and fold back the carpeting.