Cleaning and replacing the fuel filter (BMW 7 Series E38)

Petrol models

The fuel filter is located under the left side member and is accessible from underneath the vehicle.

1. Jack up the car and place it on supports. Remove the lower engine compartment cover.



2. Remove the trim in the area of the fuel filter and clamp the hoses near the filter.

3. Loosen the clamps and remove the hoses from the fuel filter.



4. Loosen the filter mounting strap tightening bolts and replace the filter.

The arrow on the filter housing must point towards the engine.

5. Secure the filter, put the hoses on it, tighten their clamps and remove the clamps from the hoses.

6. Set the parking brake, put the transmission in neutral, start the engine and check for fuel leaks.

7. Install the removed protective covers and lower the vehicle to the ground.

Diesel models

Rubber parts (for example, hoses) are subject to damage when in contact with diesel fuel.

Cleaning the filter

1. Attach a hose with an internal diameter of 8 mm to the water drain nipple on the fuel filter and place a container under the hose to collect the flowing water.



2. Loosen the nut under the fuel filter a few turns by hand and drain about 200 ml of water (until clean diesel fuel comes along). Tighten the nut.

3. Pressing the wire fastener, remove the fuel line leading to the high-pressure fuel pump from the top of the filter.

4. To bleed air from the fuel filter, have an assistant crank the engine with the starter until fuel begins to come out of the filter.

5. Put the fuel line of the high-pressure fuel pump on the filter. If necessary, replace the damaged gasket, having previously lubricated it with Vaseline.

6. Start the engine and rev it up a few times. After that, there should be no bubbles in the fuel flowing through the transparent fuel line to the high-pressure fuel pump. There should also be no fuel leaks.

Filter replacement

1. On M51 engine models, empty the filter as described above and unscrew it from the flange. Proceed to paragraph 4.





2. On models with an engine M57 or M67 press the retaining springs and simultaneously disconnect the fuel lines. On models with an engine M67 additionally, disconnect the connector (2) and release the fuel line (3) from the clamps. Loosen the nuts (4) and remove the fuel filter assembly (5).



3. Disconnect the fuel filter (1) from the unit (2).

4. If you cannot unscrew the filter by hand, use a strap wrench.

5. Fill the filter to the brim with diesel fuel and tighten it by hand until the gasket fits against the flange, then tighten it another half turn.

6. Installation is carried out in reverse order.

7. Bleed air from the filter, preventing the fuel injection pump from running without fuel.

8. Start the engine and check for fuel leaks.