MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
188
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Fig. 4-5-26 Checking the open end of piston
ring
(2) Apply some lubricating oil to the surface of cylinder
bore, connecting rod bearing shell, crank pin, piston
ring and piston.
Mobil API CI-4 lubricating oil
(3) Stagger the open ends of piston rings. After the
installation, check the positions of the open ends of
piston rings, as shown in Fig. 4-5-26.
(4) Use the piston ring compressor to install the piston
and connecting rod assembly in each cylinder. See Fig.
4-5-27.
Piston ring compressor: 5-8840-9018-0.
Piston cylinder clearance
0.07~0.09mm
Attention:
The frond end mark on the piston top
should face the front of diesel engine.
Fig. 4-5-27 Installing the piston connecting
rod group
Fig. 4-5-28 Installing the connecting rod cover
Reinstalling the connecting rod cover
⑤
Attention:
——Before the installation, check the connecting rod
bolts for any distortion, stretching or thread slipping. If
necessary, replace them.
——Reinstall the connecting rods and connecting rod
covers as the same as before.
(1) During the installation, the forward mark on the
connecting rod cover should face the front of
crankshaft.
(2) Install the connecting rod cover and connecting rod
bolts, and screw down the bolts as per the specified
torque by two steps. See Fig. 4-5-28.
Tightening torque for connecting rod bolt
Step 1 (touching torque)
Step 2 (final torque)
25N·
m±3N·
m
Turning angle 90°±5°
Clearance between connecting rod big end and
crankshaft crank
0.22~0.37mm
Open end of first
compression ring
Spiral supporting
spring port
Open end of
oil ring
Front end
mark
Open end of second
compression ring
Fro
n
t
s
id
e
Forward mark