GF47.10-P-2000MLK Component Description For Fuel Tank

GF47.10-P-2000MLK Component Description For Fuel Tank
- MODEL 171.473 with ENGINE 113.989 as of Model Year 09 /AEJ 08 model refinement package





Sectional view of fuel tank
45 Fuel filler neck
55/2 Fuel filter with fuel pressure regulator
55/2a Fuel pressure regulator
75 Fuel tank
B4 Fuel level sensor
M3 Fuel pump

Location
The fuel tank is located at the front of the trunk above the rear axle.

Design
The fuel tank has a filling capacity of about 70 liters, and is made of sheet steel.

Inside the tank are several baffle plates to prevent fuel noises.

When the fuel tank is full, a float with flap closes off the fuel filler neck. This ensures that the refueling nozzle shuts off more rapidly and overfilling is largely prevented.

At the side of the fuel feed module is a fuel level indicator sensor for detecting the fuel level.

At the bottom of the fuel pump assembly is a suction jet pump, which fills the fuel feed module when the fuel level is low. This is supplied directly by the fuel pump through a separate fuel line.

The housing of the fuel delivery module serves as a swirl pot. While cornering when the fuel level is low, the swirl pot prevents the fuel pump from drawing in air.

A coarse filter is installed in the feed line to the fuel pump.

Function
Fuel feed
The fuel pump draws fuel from the bottom of the fuel feed module through a fuel strainer, and pumps it through the fuel filter with integrated fuel pressure regulator to the fuel distribution rail (one-line system). The fuel pressure is limited to about 3.8 bar by the fuel pressure regulator. The fuel return from the fuel pressure regulator flows back into the fuel feed module.

Aeration/ventilation, except code (494) USA version
The fuel tank is aerated/vented through the vent valve, the aeration/ vent line and the activated charcoal canister.

Ventilation
The vent valve opens at an overpressure of about 30 to 50 mbar in the fuel tank, and the fuel vapors flow through the aeration/vent line to the activated charcoal canister.

Air admission
The air admission valve opens when there is a vacuum of ca. 1 to 16 mbar in the fuel tank and air or fuel vapors are suctioned over the activated charcoal canister.

Refueling
The vent valve opening pressure of about 30 to 50 mbar is not reached when the tank cap is removed. The vent line to the activated charcoal canister remains closed off. This means that the nozzle switches off quicker.

Aeration and ventilation with code (494) USA version
The fuel vapors flow through the two safety valves (rollover valves) placed at the top, and through the aeration/vent pipe and the aeration/vent line to the activated charcoal canister.

The safety valves close off the ventilation system if there is an accident, thus preventing fuel from flowing into the activated charcoal canister.

Emptying
The fuel tank has no outlet valves. It is emptied by the related air extractor system.