Fuel system
40
Powerplant
g
Introduction of the New G-Class, Model Series 463
M 273
The fuel pump suctions the fuel out of the feed module
and pumps it through the filter to the fuel distribution
rail (single-line system). In the process, the pressure is
regulated by the FSCM. The fuel pressure sensor
B4/7 continuously reports the current fuel pressure to
the FSCM.
There is a check valve at the feed point of the fuel filter
which prevents reduction of the pressure when the
fuel pump is switched off.
The fuel return from the pressure limiting valve drives
the suction jet pump, which is located in the right the
fuel tank. This suction jet pump pumps the fuel from
the right side of the tank to the centrally located feed
module.
OM 642
Fuel supply on the OM 642 is carried out by an electric
fuel pump, which pumps the diesel fuel into the engine
compartment to a mechanically powered high-pres-
sure pump. The electric fuel pump is a roller vane
pump which is adapted to the quantity requirements
and system pressure of the high-pressure pump.
The fuel supply system is equipped with a feed and
return line, whereby the electric fuel pump provides
the flush volume for the high-pressure pump and
enough fuel for wide-open throttle operation of the
engine via the feed line.
Any excess fuel is directed via the leak oil lines which
are connected directly to the injectors back to the
tank via the return lines.
– This printout will not be recorded by the update service. Status: 03 / 2012 –
