How to Replace the Fuel Pump on a 450SL

Fuel Pump Replacement
1. Before attempting to remove the old fuel pump, disconnect the negative battery cable using a 12-mm socket. Place a block under the front wheels to prevent rolling. Locate the electric fuel pump under the rear floor panel. Jack up the left rear of the car and support it on a jack stand. This will provide plenty of room for you to remove the fuel pump.
2. Remember that gas is highly flammable, so keep a fire extinguisher nearby. Using a Phillips screwdriver, remove the intake and outlet hoses from the fuel pump. Use bolts to plug up the inlet and outlet hoses to prevent gas from leaking.
3. Using an 8-mm socket, disconnect the negative and positive wires from the fuel pump. Unbolt and remove the fuel pump and vibration pads with a 14-mm socket. Compare the old fuel pump to the new one to ensure that you are installing the correct replacement part.
4. Install the new fuel pump. Secure it to the Mercedes-Benz 450SL using the 14-mm socket. Connect the brown negative wire to the negative brown terminal and the positive red/black wire to the red positive terminal on the fuel pump. Using the Phillips screwdriver, connect the inlet and outlet hoses to the fuel pump. If a secure connection cannot be made, you may need to replace the hose clamps.
5. Remove the jack stand and lower the vehicle to the ground. Reconnect the negative battery cable and start the car. Check under the rear floor panel for fuel leaks.