Chapter VI Fuel System
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
389
Fig. 6-1-13 Installing the XINFENG M680
high-pressure fuel pump
Fig. 6-1-14 DELPHI High-pressure fuel rail
assembly
Fig. 6-1-15 BOSCH High-pressure fuel rail
assembly
(3) It is strictly forbidden to add an automatic fuel
delivery device before the high-pressure fuel pump.Or
else, the proportional solenoid valve will be damaged.
(4) A high precise couple is installed in the
high-pressure fuel pump. If a failure occurs, send the
pump to a professional maintenance department for
check and repair instead of removing it randomly.
2.3.5 Installing the High-pressure Fuel Pump
(1) Plug the fuel return pipe subassembly in the fuel
return pipe connector of high-pressure oil pump.
(2) Install the high-pressure oil pump, and tighten 2
hexagon flange bolts (M8×30) and a hexagon flange
nut with required torques. See Fig. 6-1-11, Fig. 6-1-12
and Fig. 6-1-13.
Tightening torques for the fastening bolts and nuts
of high-pressure fuel pump:
23 N•m ± 3 N•m
2.4 High-pressure fuel rail
The high-pressure fuel is included in the high-pressure
fuel rail.The fuel supply in high-pressure fuel pump and
the high-pressure oscillation generated by fuel injection
attenuate in the high-pressure fuel rail volume, so as to
ensures that the injection pressure maintains a fixed
value when fuel injector is opened.The high-pressure
fuel rail meanwhile serves as a fuel distributor. One of
the fuel pipe connectors is used as a fuel inlet hole on
the high-pressure fuel rail. The high-pressure fuel pump
is connected with the high-pressure fuel pipe and other
4 fuel pipe connectors are connected with the fuel
injectors. See Fig. 6-1-14.The rail pipe shall be
attached to diesel engine and shall not run by
suspending in the air, or else the common-rail system
will be damaged.It is not allowed to disassemble the
safety valve for regulation without permission.The rail
pressure sensor is a electronic component which shall
not
be
knocked
or
disassembled
without
permission.During the its application, the inside of the
fuel rail must be kept clean without the entry of water,
so as to avoid getting rusty.
2.4.1 High-pressure Fuel Rail of DELPHI System
For the high-pressure fuel rail of DELPHI system, see
Fig. 6-1-14.
Technical parameters of DELPHI high-pressure
common rail:
High pressure range: 1600-1800-2000 bars
Fuel distribution from fuel pump to fuel injector:
repeated fuel injections are assisted by means of flow
calibration together with damp optimization.
Cylinder body
High-pressure
fuel rail
Inlet hole of fuel
rail
Outlet hole of
fuel rail
Rail pressure
sensor
High-pressure
fuel rail
Rail pressure
sensor
Fuel from
high-pressure
fuel pump
High-pressure
fuel pipe to
fuel injector
