Doosan DP180L Series - How to Maintain Turbocharger

9. Intake/exhaust system
145
How to Maintain Turbocharger
1. Cautions for engine operation
1) Observe the followings when starting, operating, and
stopping an engine.
Item Cautions Reasons
Starting an engine
1) Check the oil amount
2) Therefore, start the engine with the starter motor
to check the rise of oil pressure (until the gradation
of the oil pressure gauge moves or the pressure
indicator lamp is turned on).
2) Overhasty start of engine leads to engine
rotation without lubricating turbocharger
and other engine parts, causing abnormal
wear or burning of bearings.
3) If you replace oil, oil filter cartridge, or lubrication
system parts or use an engine in cold areas, or the
engine has stopped for a long period, loosen the oil
pipe joint at the inlet of the turbocharger and run
the starter motor until oil flows out. After completing
the work, tighten the oil pipe joint again and start
the engine.
3) When an engine has stopped or kept
cold for a long period, circulation of oil in the
pipe gets poor.
After starting an engine
1) Operate the engine at idle for five minutes from
starting it.
1) When the engine is suddenly loaded
while the engine and the turbocharger have
not been smoothly rotated after starting the
engine, parts with insufficient oil may be
burnt.
2) Check if oil, gas, or air is leaked from each part.
If so, take proper action.
2) Leakage of oil, gas, or air (especially oil)
reduces oil pressure and loss of oil cause
burning of bearings.
During Operation
check the following.
1) Oil pressure
At idle: 1.5 ~ 3.0 kg/cm
2
Fully loaded: 3.0 ~ 5.5 kg/cm
2
1) Too low oil pressure causes abnormal
wearing or burning of bearings. Too high oil
pressure causes oil leakage.
2) When abnormal noise or vibration occurs, slowly
reduce the rotate count until the engine stops and
then figure out the causes.
2) Operating an engine with noise or vibra-
tion may cause irreversible damage of the
engine.
Stopping an Engine
1) Operate the engine at idle for five minutes before
stopping it.
1) Sudden engine stop after operating the
engine under high load allows the heat from
the red-heated turbine blade to be delivered
to the bearing system. Then oil burns and
the bearing metal and rotation shaft are
burnt.