MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
166
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Fig. 4-4-22 Upper and lower main shaft
bearing shells
Fig. 4-4-23 Installing the crankshaft position
signal panel
Attention:
All the upper main bearing journals (on
the side of the upper cylinder body) have oil grooves and
oil holes, and all the lower main bearing journals (on the
side of the lower cylinder body) are without oil grooves or
oil holes. However, special attention should be paid
during installation. See Fig. 4-4-22.
(2) Install the crankshaft position signal panel to the 8
th
crank arm of the crankshaft, and screw down the 3
hexagon lobular socket countersunk head screws
(M6×12) as per the specified torque. There should be no
deflection or improper mounting. See Fig. 4-4-23.
Tightening torque for hexagon lobular socket
countersunk head screw
9 N·
m±3 N·
m
(3) Apply an appropriate amount of lubricating oil onto the
main bearing journal and into the oil hole of the
crankshaft. Install the crankshaft to the upper cylinder
body.
Mobil API CI-4 lubricating oil
Fig. 4-4-24 Installing the lower cylinder body
Reinstalling the lower cylinder body
⑩
(1) Apply an appropriate amount of lubricating oil
between the crankshaft thrust plate and the crank arm
thrust surface.
Mobil API CI-4 lubricating oil
(2) Respectively install the upper and the lower thrust
plates onto the upper and the lower cylinder body
rabbets, with the oil groove sides of them oriented to the
crank arm.
Attention:
There is no positioning lip for the upper
thrust plate, while there is for the lower thrust plate.
(3) Evenly apply sealant to the top surface of the lower
cylinder body, and install the 10 main bearing cap bolts
(M11×1.5×87) and the 11 hexagon flange face bolts
(M8×80) of the lower cylinder body after they were
aligned to the dowel pins of the upper cylinder body, then
orderly screw down them in 3 steps as per the specified
Upper main shaft
bearing shell
Lower main shaft
bearing shell
Crankshaft position
signal panel
Flywheel gear
ring assembly
Crankshaft
Lower cylinder body
Upper cylinder body