MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES
44
Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited
Figure 2-8-20 Checking the oil level with an
engine oil dipstick
should not be below the lower scale mark, because it will
result in that the oil pump cannot pump up the oil. It is
also not appropriate that the oil level is higher than the
upper scale mark, because the crank of crankshaft will
strike on the surface of oil, which will cause malfunctions
such as oil consumption increase, exhaust deterioration,
serious carbon deposit on the piston top and the
combustion chamber walls, and piston ring stuck due to
coking, etc. Therefore, in addition to the oil pressure, the
oil level also should be checked with the dipstick before
traveling and per 300 ~ 500 km of traveling distance.
Attention:
In addition to checking the oil pressure,
the oil level also needs to be checked before traveling.
5.3 Replacement with New Oil
After the oil is used for a long time, there are not only
impurities and dust, but also unburned fuel which makes
the oil thinner. Some exhaust gas enters and brings
anhydride which deteriorates the oil and then corrodes
the parts; therefore, after the oil has been used for some
time (e.g. after the vehicle traveling distance
accumulates to 8000 ~ 10000 km), the oil should be
overall replaced.
Method to replace the engine oil:
(1) Place the diesel engine or park the vehicle in a flat
location.
(2) Run the diesel engine, and stop it when the oil
temperature reaches 80
℃
.
Fig. 2-8-21 Screwing the oil drain screw plug
and draining out the engine oil
(3) Place an oil collection pan under the engine, unscrew
the oil drain screw plug (see Fig. 2-8-12), drain out the oil
in the oil pan.
Warning:
Take care of hot oil so as to avoid burning,
and dispose the used oil properly to protect the
environment.
(4) Place a new sealing ring, screw the oil drain screw
plug and tighten it according to requirements, add new
engine oil and check the oil level with the dipstick.
Tightening torque for oil drain screw plug
40 N·
m ± 5 N·
m
If a large number of impurities deposit in the oil pan, the
lubrication system should be washed with 5# and 7#
machinery oil (light spindle oil) when the new engine is
running in, petrol or kerosene is not allowed.
When cleaning the inner side of diesel engine, fill the oil
pan with 5# or 7# machinery oil, the oil level should be at
the center of lower and upper scale marks on the
Engine oil
dipstick
Upper scale
mark
Lower scale
mark
Engine
oil
dipstick guide
Oil
collection
pan
Copper
washer
Oil
drain
screw plug
