Operation In Winter; Cold Start; Preventing Coolant From Freezing; Preventing Over Cooling Of The Engine - Doosan DP158L Series Operation & Maintenance Manual

Operation in winter

Cold Start

1. The preheat lamp turns on when the key switch is set to
"ON." When the preheat lamp goes off, proceed as
follows. The pre-heater device activates when the coolant
temperature is below 25°C, and the preheating system is
automatically adjusted based on the coolant temperature.
(The max. preheating time is around 25 seconds) It does
not activate when the coolant temperature is over 25°C.
CAUTION
The engine is equipped with a preheating system for
enhancing cold start ability.
2. In order to start the engine after the preheat lamp turns
off, turn the key switch to the ignition position. When the
key switch is turned to the ignition position, the pre-heater
plug or air heater runs continuously to make starting the
engine easier and reduce white exhaust gas. If the
coolant temperature is over 25°C, it is not necessary to
operate the pre-heater plug or air heater.
3. When the engine starts, set the key switch in the ON posi-
tion. The timer runs for another 5 minutes even after the
engine starts to heat the intake air and quickly eliminate
white exhaust gas.
CAUTION
Do not run the start motor for over 10 seconds. If the
engine still cannot be started after preheating, wait for
30 seconds and then perform preheating again before
the second attempt to start the engine.

Preventing Coolant from Freezing

When only water used as coolant without mixing with anti-
freeze, corrosion in the engine, degradation of cooling effi-
ciency, and freezing of the engine in winter may occur. If the
engine is not operated for a long period during cold weather
or in areas with cold climate, fully discharge the coolant from
the engine. Freezing of coolant leads to critical damage to
the engine. Please use a mixture of coolant with antifreeze at
revised ratio when replacing or replenishing the coolant. The
antifreeze prevents coolant from freezing.
2. Operation and maintenance

Preventing Over cooling of the Engine

When the engine is cooled below the normal operating
temperature, thermal efficiency is lowered and fuel
consumption as well as abrasion of the cylinder liner may
increase. Therefore, the engine should be operated within
the normal operating temperature. If the engine has been
sufficiently operated, but the temperature of coolant remains
below the normal operating temperature, check the water
temperature controller or other parts related to the cooler.

Engine Oil

When viscosity of engine oil increases due to its low
temperature during cold weather or in areas with cold
climate, the rpm may not be stable after starting the engine.
To prevent this, replace oil to engine oil for cold weather or
areas with cold climate. When replacing engine oil, use of
Doosan genuine engine oil is recommended.
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