Komatsu D31EX-21, Руководство по эксплуатации и техническому обслуживанию, Страница: 203 / 256

MAINTENANCE
SERVICE PROCEDURE
4-23
CLEAN INSIDE OF COOLING SYSTEM 4
WARNING
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Just after the engine is stopped, the cooling water is still hot and the internal pressure in the radiator
is still high. If the radiator cap is removed under this condition, you may scald yourself. Accordingly,
wait until the temperature goes down, then loosen the cap slowly to release the pressure.
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Start the engine to clean the cooling system. When standing up from the operator's seat or leaving the
machine, set the safety lock lever and brake lock lever to the LOCK positions.
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For the starting method of the engine, see “CHECK BEFORE STARTING ENGINE, ADJUST (3-61)“ and
“STARTING ENGINE (3-77)“ in the OPERATION section of the manual.
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Never go under the machine body while the engine is running. It is very dangerous since the machine
may move suddenly.
Stop the machine on level ground when cleaning or changing the coolant.
When flushing the inside of the cooling system, do as follows.
Use a permanent type of antifreeze.
If, for some reason, it is impossible to use permanent type antifreeze, use an antifreeze containing ethylene glycol.
The ratio of antifreeze to water depends on the ambient temperature, but to obtain the corrosion resistance effect,
a minimum ratio of 30% by volume is necessary.
When deciding the ratio of antifreeze to water, check the lowest temperature in the past, and decide from the mix-
ing rate table given below.
It is actually better to estimate a temperature about 10°C lower when deciding the mixing rate.
Kind of coolant
Cleaning inside of cooling system
and changing coolant
Replace corrosion resistor
Permanent type antifreeze
(All season type) Every year (autumn) or every 2000
hours whichever comes first
Every 500 hours and when cleaning
the inside of the cooling system and
when changing coolant Non permanent type antifreeze con-
taining ethylene glycol
(Winter, one season type) Every 6 months (spring, autumn)
(Drain antifreeze in spring, add anti-
freeze in autumn)
When not using antifreeze
Every 6 months or every 1000 hours
whichever comes first