Doosan AD158TI, Operation & Maintenance Manual

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General information - 34 -
Any coolant loss due to engine operation must be replenished. But adding fresh water for coolant tends to
lower the content of anti-freeze. Always replenish the coolant with a mixture of antifreeze and water, and
keep the proper content of antifreeze (35 ~ 40%).
4.3.4. Heat exchanger and cooling line cleaning
(1) Heat exchanger cleaning
If the heat exchanger tubes are clogged by
many small pieces or polluted by corro-
sion, the sea water quantity will be
reduced gradually also as a result of it
engine overheating may be occurred.
a) Remove the heat exchanger both left
and right side covers.
b) Remove the clogged small pieces and
clean the heat-exchanger tubes.
When the heat-exchanger tubes do
cleaning, clean outside and inner side
of tubes with a small wire brush and
pressurized water.
(2) Fresh water line cleaning
If the cooling circuits are fouled with water scales or sludge particles, the cooling efficiency will be
dropped down.
The poor condition of the cooling system is normally due to use of unsuitable anti-freezing agents so
periodically clean the circuit interior with a cleaner
Cooling system cleaning interval : Every 1,200 hours
Ambient
temperature (°C)
Fresh water (%) Anti-freeze (%)
Over -10 85 15
-10 80 20
-15 73 27
-20 67 33
-25 60 40
-30 56 44
-40 50 50
EDV2218161