GF47.00-W-0002MB | Fuel supply - function | 5.8.04 |
ENGINE 457.9 in MODEL 374.6 with BODY 374.870, 944.890
ENGINE 457.9 in MODEL 375.4 with BODY 375.860
ENGINE 457.9 in MODEL 940, 942, 943, 944 with BODY 944.890
ENGINE 457.9 in MODEL 958.4 with BODY 958.880
W47.00-1024-76
2.1 Manual fuel feed pump
- Only for vehicles without code (K81) Fuel prefilter with heated water separator
3.1 Assembly valve in fuel feed flow (opened by pressure
3.2 Assembly valve in fuel return flow (opened by pressure)
4 Fuel heat exchanger
5 Fuel pump
6 Fuel filter
7 Nozzle holder combination
8 Pressure holding valve (2.0 bar)
9 Pressure pipe connection
Y6 Cylinder 1 unit pump
Y7 Cylinder 2 unit pump
Y8 Cylinder 3 unit pump
Y9 Cylinder 4 unit pump
Y10 Cylinder 5 unit pump
Y11 Cylinder 6 unit pump
A Suction or vacuum side fuel feed line
D Fuel return line
E Fuel short circuit line
B Fuel feed line, pressure side
C Fuel high-pressure line
General information
The fuel supply ensures that the fuel required for combustion is available under all operating conditions in the sufficient quantity, at the correct time and with the required pressure.
Fuel to the individual cylinders is supplied through the Pump Line Nozzle System (PLD System), which is provided with fuel by the fuel low pressure circuit.
Fuel low pressure circuit
The fuel low pressure circuit ensures that the fuel is cleaned and provided to the unit pumps of the PLD System in the sufficient quantity and with the required pressure.
It basically consists of the following components:
Fuel tank
Manual fuel feed pump (2.1)
- Only for vehicles without code (K81) Fuel prefilter with heated water separator. For vehicles with code (K81) Fuel prefilter with heated water separator the manual fuel feed pump is in integrated in the fuel prefilter.
Fuel heat exchanger (4)
Fuel pump (5)
Fuel filter (6)
Pressure holding valve (8)
Suction or vacuum side fuel feed line (A)
Pressure side fuel feed line (B)
Fuel return lines (D)
Fuel short circuiting line (E)
Pump Line Nozzle System (PLD System)
The fuel provided by the fuel low pressure circuit through the PLD system is injected into the cylinders in the adequate quantity, at the correct time and with the correct pressure.
The Pump-Line-Nozzle system consists of unit pumps for cylinder 1 to 6 (Y6 to Y11), injection nozzles in the nozzle holder combinations (7), pressure pipe connections (9) and the high pressure fuel lines (C), over which the individual unit pumps are connected with the respective injection nozzles.
The excess fuel delivered during the fuel high pressure delivery goes back to the fuel low pressure circuit via the fuel return lines (D).