Replace / drain fuel filter

No special tools required.

Wear part required:

• Fuel filter for the respective engine.

  When purchasing, state model year and vehicle model.

• Diesel: O-ring for the filter.

Petrol engine

Replace fuel filter

When removing the fuel filter, a larger amount of fuel may leak out. A fuel-resistant container is therefore required to catch it.

Removal

Warning: No open flames, fire hazard! Keep a fire extinguisher ready.

• Disconnect the battery negative (-) cable from the battery. Caution: this will erase electronic memories, such as engine operating values.

  Observe the notes in the chapter "Removing and installing the battery".

• The filter is located on the underbody in front of the fuel tank, near the right rear wheel. Raise the rear of the vehicle on stands and remove the cover screws - arrows -.

• Place a suitable catch container under the fuel filter.

• Thoroughly clean the fuel connections before loosening them, for example with cold cleaner and a brush.

• Wrap a cloth around the fuel lines. Pull off the fuel lines, pressing the side clips of the quick-release couplings - 1 - together with your fingers.

• Loosen the retaining clip - arrow - of the filter.

• Remove the fuel filter. Note the installation position of the filter for reinstallation.

Installation

• Install the fuel filter in the same position as removed.

  The flow direction is marked with an arrow - 2 - on the filter housing; it points from the tank toward the engine. 1 - inlet connection; 3 - outlet connection.

• Tighten the retaining clip screw.

• Push on the fuel supply and return lines; the quick-release couplings will engage with a click.

• Fit the plastic cover.

• Connect the battery negative cable (-).

  Set the clock, if fitted, and enter the radio anti-theft code.

• Lower the vehicle.

• After running the engine, check the fuel connections for leaks.

Diesel engine

Drain / replace diesel fuel filter

A suitable catch container is required to collect the water.

Caution: Leaked diesel fuel must be wiped off rubber parts (e.g. coolant hoses) immediately, otherwise the rubber parts will be damaged over time.

Draining

• During maintenance, drain filter - a -.

  Place a suitable drain pan under the drain screw - b -.

• To let the fuel drain more easily, unscrew bleed screw - c -.

  Loosen the drain screw and let the liquid drain until water-free fuel flows out. Finally, only clean diesel fuel should emerge.

• Tighten the drain screw and bleed screw, then remove the drain pan.

• Check the fuel system for leaks.

  To do so, start the engine. The fuel system bleeds itself during this process.

Filter replacement

• Drain all liquid from the filter as described for draining.

1. 1

   Filter element

2. 2

   Threaded connector

3. 3

   O-rings

4. 4

   Thermo sensor sealing ring

5. 5

   Thermo sensor (where fitted)

6. 6

   Fuel heating element (where fitted)

7. 7

   Drain plug

• Unscrew the filter element from the heating element by hand or with a strap wrench.

• Coat the rubber sealing ring of the new filter with diesel, fill the filter completely with diesel, and screw it on.

• Remove the catch container and the cover under the filter.

• Start the engine; the fuel system bleeds itself during this process. If the engine does not start, bleed the fuel system; see page 114.

• After a test drive, check the fuel system for leaks.