MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
180
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Fig. 4-5-5 Removing the oil pan upper and
lower body assemblies and oil collector
assembly
Disassembling the oil pan upper and lower body
assemblies and oil collector assembly
④
(1) Use a spanner to remove the 14 hexagon flange
face bolts (M6×12) fastening the upper and lower
bodies of oil pan in proper order, and remove the lower
body of oil pan. See Fig. 4-5-5.
(2) Use a spanner to remove the 2 hexagon flange bolts
(M6×16) fastening the engine oil pipe and the 2
hexagon flange face bolts (M8×12) fastening the oil
collector support, and remove the oil collector.
(3) Use a spanner to remove the 15 hexagon flange
face bolts (M6×20, M6×110, M8×25 and M8×45)
fastening the upper body of oil pan and lower cylinder
body in proper order, and remove the upper body of oil
pan from the lower cylinder body.
Fig. 4-5-6 Removing the piston connecting
rod assembly
Fig. 4-5-7 Removing the piston ring
Disassembling the connecting rod cover
⑤
(1) Respectively remove the 8 connecting rod bolts
tightening the connecting rod cover under the
crankshaft, and take down the 4 connecting rod covers
and 4 lower connecting rod bearing shells. See Fig.
4-5-6.
(2) Place the parts removed from each cylinder orderly
and make the corresponding marks. All parts must be
reinstalled to the original positions during the
reinstallation.
(3) Check the thread of the connecting rod bolts for
damage or stretching, and replace them if damaged.
Disassembling the piston and connecting rod
assembly
⑥
(1) Before removing the piston and connecting rod
assembly, use a scraper to clear away the carbon
deposits on the cylinder wall.
(2) Move the piston to the top of the cylinder and push
the lower part of the connecting rod with a hammer
handle or something similar; take out the piston and the
connecting rod.
Caution:
Do not damage the connecting rod
bearing journal and the inner surface of cylinder during
removal.
Disassembling the piston ring
⑦
(1) Use the piston ring expander to respectively remove
the second compression ring and the first oil ring. See
Fig. 4-5-7.
Upper body of
oil pan
Oil collector
Lower body of oil
pan
Piston
Connecting
rod
Connecting rod
cover
Crankshaft