MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
434
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Fig. 8-2-12 Removing the engine oil dipstick
and its guide
Fig. 8-2-13 Removing the lower body of oil
pan
Fig. 8-2-14 Removing the oil pump assembly
dipstick subassembly fastening on the timing hood.
(3) Pull out the oil dipstick guide subassembly from the
oil pan as shown in Fig. 8-2-12.
Removing the lower body assembly of oil pan
⑤
(1) Remove 14 hexagon flange bolts (M6 x 12)
fastening the lower and upper bodies of oil pan with
spanner orderly as shown in Fig. 8-2-13.
(2) Take off the oil pan lower body from the upper body.
Removing the oil pump assembly
⑥
(1) Remove 10 hexagon bolts and flat ring components
(M8×40, M8×25 and M8×20) fastening the engine oil
pump assembly and cylinder body in proper order, and
take off the engine oil pump assembly. See Fig. 8-2-14.
(2) Take out the outer rotor of oil pump and rubber seal
ring from the oil pump chamber of upper cylinder body.
See Fig 8-2-14.
(3) Take out the front oil seal of crankshaft through the
oil seal hole of oil pump crankshaft.
Front oil seal stripper: 5-8840-2362-0.
Inspection and repair
(1) Replace the oil pump assembly when the rotor is
found to be seriously worn or damaged. See Fig.
8-2-15.
(2) Replace the oil pump assembly if the pressure
limiting valve is found to be blocked.
Installation
Installing the oil pump assembly
⑥
(1) Apply a little lubricating oil on the seal ring of oil
pump and insert the seal ring into the end of
corresponding groove of oil pump housing without
scratch, deflection and misplacement.
(2) Coat the front oil seal of crankshaft with an
appropriate amount of lubricating oil, and install it to the
oil seal hole of the engine oil pump housing. After the
installation, there should not be any scratch, deflection
or misplacement.
Installer of front oil seal: 5-8840-2361-0.
(3) Apply an appropriate amount of lubricating oil to the
inner surface of engine pump external rotor, and install
the external rotor to the engine pump cavity of the upper
cylinder body with the marks of internal and external
rotors on the same side. See Fig. 8-2-15.
Mobil API C1
– 4 lubricating oil.
Upper body of
oil pan
Outer rotor
Seal ring
Front oil seal
Lower body of
oil pan
