Doosan DX35Z, Operation And Maintenance Manual

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OP000471 Inspection, Maintenance and Adjustment
4-50
ENGINE COOLING SYSTEM
General
Keeping an engine's cooling system in peak operating
condition can have many benefits in 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.
Make at least a minimum mixture of 40% antifreeze with
60% distilled water for adding additional fluid to the system
during normal maintenance. This level will help maintain the
additive concentration of the system. Check the coolant
every 500 hours.
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.
CAUTION!
Maintaining the proper anticorrosive additive levels in
antifreeze will help protect the engine and other
components from becoming corroded.
If anticorrosive additive levels are not properly
maintained and monitored, server damage to the cooling
pump and cylinder liners may result. This corrosion can
also result in the radiator tubes becoming clogged and
loosing their heat transfer efficiency. The engine (Model:
DV11) uses a wet-type cylinder liner design, which
requires, a high efficiency cooling system flow, to
maintain proper engine temperatures.
The coolant and its additives can be checked by using
coolant test paper (No: 60.99901-0038).