Doosan DL200, Operation And Maintenance Manual

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OP000509
4-75
Inspection, Maintenance and Adjustment
ENGINE COOLING SYSTEM
General
Keeping an engine's cooling system in peak operating
condition, can have many benefits to keeping a machine in
good operating condition. A properly functioning cooling
system will; improve fuel efficiency, reduce engine wear, and
extend component life.
Always use distilled water in the radiator. Contaminants in
tap water neutralize the corrosion inhibitor components. If
tap water must be used, it should not exceed 300 ppm
hardness, or contain more than 100 ppm of either chloride
or sulfate. Water that has been treated with a water softener
also contains salt that will cause corrosion of components.
Water from creeks and stagnant pools usually contains dirt,
minerals and/or organic material that are deposited in the
cooling system and impair cooling efficiency. Distilled water
is the best.
Engine overheating is often caused by bent or clogged
radiator fins. The spaces between the fins can be cleaned
by use of air or water under pressure. When straightening
bent fins, use care not to damage the tubes or break the
bond between the fins and the tubes.
Heavy duty diesel engines require a balanced mixture of
water and antifreeze. Drain and replace the mixture every
year or 2,000 hours of operation, which ever comes first.
This will eliminate buildup of harmful chemicals.
Antifreeze is essential in any climate. It broadens the
operating temperature range by lowering the coolant's
freezing point and by raising its boiling point. Do not use
more than 50% antifreeze in the mixture unless additional
freeze protection is required. Never use more than 68%
antifreeze under any condition.
WARNING!
Pressure at air nozzle must not exceed 2.1 kg/cm
2
(30
psi). Always wear goggles when using compressed air.
Do not pour cold water into radiator when engine is
very hot and water level is below the top of the tubes.
Such action could result in damage to engine cylinder
heads.