16 00 005 Draining and filling fuel tank
| IMPORTANT | Observe country-specific safety regulations. Make sure the work bay is adequately ventilated. Connect an exhaust extractor system to exhaust tailpipe. Do not allow the electric fuel pump to run dry! Carefully withdraw extraction hose so as not to damage non-return flap. The electric fuel pump must not operate without fuel! On conclusion of repair work and before starting the engine for the first time, the fuel tank must be filled via the fuel filler pipe with at least 5 liters of fuel. |
Note. Vehicles with W17 engine
Before starting the engine for the first time, if the tank has been run dry or drawn off, fill with diesel fuel and turn on ignition for approx. 1 minute. The fuel circuit is thus filled and vented, which results in the engine firing more quickly.
Drawing Off Fuel
Start engine and allow to run. The electric fuel pump runs.
The pump delivers fuel via the suction jet pump and the tank expansion line from the left to the right side of the fuel tank.
Fuel can be drawn off from the left and right tank halves through the fuel filler pipe down to a small residual amount. This residual amount is drawn off after removal of the sensors for the fuel gauge (right/left).
Feed suction hose of extractor unit into filler pipe. In so doing, turn hose slightly if necessary.
Insertion Length
90 cm.
Draw off fuel with extractor unit as far as possible.
Observe the fuel gauge in the instrument cluster while extracting fuel.
Drawing Off Residual Fuel Quantity
| IMPORTANT | Make sure vehicle interior is adequately ventilated. Catch dripping fuel in a suitable container. |
Remove (right) fuel gauge sensor. Refer to 16 14 017 REMOVING AND INSTALLING/REPLACING FUEL FILTER WITH FUEL LEVEL SENSOR .
Remove (left) fuel gauge sensor. Refer to 16 14 015 REMOVING AND INSTALLING/REPLACING FUEL PUMP WITH FUEL LEVEL SENSOR .
Draw off residual fuel quantity through installation openings.
Fuel Filling
Feed suction hose of extractor unit approx. 40 cm into fuel filler pipe.
Fill fuel from suction extractor unit.
Extracting Fuel After A Defect In The Suction Jet Pump
Completely empty left half of fuel tank via fuel filler pipe.
Remove (right) fuel gauge sensor. Refer to 16 14 017 REMOVING AND INSTALLING/REPLACING FUEL FILTER WITH FUEL LEVEL SENSOR .
Insert extractor hose through installation opening of sensor into the fuel tank. The fuel (also residual quantities) can now be drawn off.