MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
26
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Section VI Maintenance Standard for Engine
The normal operation of engine usually means: the consumption rates of fuel and lubricating oil conform
with the design specifications, and the engine is capable of producing its designed power and running
smoothly without abnormal noise. Any abnormal phenomenon has a relation with the fitting condition of
the kinematic pair of engine. There are strict technical requirements for the assembly of kinematic pairs
of engine; the geometric shape, fit clearance, surface roughness and cleanliness of parts should
conform with the requirements. When the matching parts are installed, certain precisions should be
applied, and the fit clearances are especially important. If the clearance is too small, the engine can not
run smoothly, which accompanied with friction increasing, overheat, galling, even blockage if serious; if
the clearance is too big, it may create impact and noise shortly after the parts are used, and result in
difficulty in forming lubricating oil film, thus decreases the service life of parts. For the diesel engine that
is put into service after strict assembly and running-in, its service life lies on proper maintenance.
1. Tightening Torque of Main Fasteners of Engine
For the tightening torque of main fasteners of GW4D20/GW4D20B turbocharged diesel engine, see
Table 2-6-1.
Table 2-6-1 Tightening Torque of Main Fasteners of GW4D20/GW4D20B Turbocharged Diesel
Engine
Sequence
No.
Parts Code
Parts Name and
Specification
Installation
Position
Tightening Torque
Value (N·
m)
1
1004303
—ED01
Connecting rod
bolt
Connecting rod
——connecting rod
cap
25 ± 3, rotation angle
90° ± 5°
2
1003700
—ED01
Bolt and washer
component of
cylinder head
Cylinder body
——cylinder head
gasket
——cylinder
head
50 ± 3, rotation angle
90°, rotating an
additional 120°
3
1021800
—ED01
Bolt and washer
component of
camshaft timing
pulley
Camshaft pulley
——camshaft
110±5
4
1005011
—ED01
Flywheel bolt
Flywheel
——camshaft
75±5
5
1002116
—ED01
Main bearing cap
bolt
Cylinder body
——main bearing
cap
40 ± 3, rotation angle
90°, rotating an
additional 90°
6
1021014
一
ED01
Bolt of crankshaft
timing pulley
Crankshaft timing
pulley
——crankshaft
185~195
7
Q1840820F32
Hexagonal flange
face bolt
Damping pulley of
crankshaft
——crankshaft
23±3
8
1009106
—ED01A Fuel drain bolt (hex Fuel pan assembly
40±5