16 00 ... Diesel Fuel Supply System
16 00 ... Diesel Fuel Supply System
1. General
General function description of fuel system. 16 00 ... Functional Description For General Fuel Supply Systems
2. Part designation
Schematic drawings of fuel supply systems
Diesel fuel supply system
1. Electric fuel pump
2. Fuel filter with electr. filter heater
3. High-pressure pump
4. Injector
5. Outlet protection valve
6. Suction jet pump, left
7. Pressure limiting valve
8. Suction jet pump, right
9. Level sensor
10. Filler vent valve
11. Service vent valve
12. Roll-over valve
13. Insect strainer
3. Functional description (see also graphic)
Fuel system
The saddle-shaped fuel tank contains the surge chamber with integrated electric fuel pump on its right side.
The surge chamber ensures that the fuel pump is properly supplied in all vehicle operating states.
The fuel is pumped from the right side of the fuel tank into the surge chamber via the suction jet pump integrated in the surge chamber.
The suction jet pump in the left fuel tank half pumps the fuel through the tank expansion line to the right side of the fuel tank.
The suction jet pump is operated via the fuel feed line.
Fuel supply to engine:
Fuel is pumped by the electric fuel pump to the injector via the fuel feed line, the fuel filter with electric heater and the high-pressure pump.
The fuel tank is vented during refueling via the filler vent valve.
Venting during vehicle operation is performed via the service vent valve.
The filler vent valve in the tank is closed by the rising fuel if the tank is overfilled. The residual volume thus created replaces the expansion tank. The ventilation function is maintained by a second float valve.
Both valves are designed as rollover valves. This prevents fuel from escaping from the fuel tank in extreme vehicle positions (overturning, inclined position).
Determining fill level in fuel tank:
The fuel level is measured by means of lever sensors on both sides of the fuel tank. The combination of the determined ohm values from the right and left lever-type sensors produces the actual level in the fuel tank.
Operating principle of electric filter heater:
The electric filter heater cuts in under the following conditions as a function of fuel pressure and fuel temperature:
- Cold, viscous fuel exceeds a specific fuel pressure (in the filter inlet).
- Fuel drops below a specific temperature (under 2 °C).
4. Operating data, fuel system
Operating pressure in rail up to 1600 bar.
Operating pressure ahead of high-pressure pump approx. 5.6 bar.