Komatsu H75051, Operation & Maintenance Manual

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METHOD FOR CLEANING INSIDE OF COOLING SYSTEM
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WARNING
• Immediately after the engine is stopped, the coolant is still hot and the pressure is accumulated in
the radiator. If the cap is removed under this condition and the coolant is drained, it may cause a
burn. Always wait for the temperature to go down, and turn the cap slowly to release the pressure.
• Start the engine and perform the cleaning. When standing up or leaving the operator's seat, set the
lock lever to LOCK position.
• For starting the engine, see OPERATION, MACHINE OPERATIONS AND CONTROLS, “CHECKS AND
ADJUSTMENT BEFORE STARTING ENGINE (3-149)”, and “METHOD FOR STARTING ENGINE
(3-174)”.
• Keep away from the rear of the machine while the engine is running. Because the engine is operat-
ed during cleaning, the machine may suddenly move, and you may be hit if you are standing behind
it.
Place the machine on a level ground when cleaning or changing the coolant.
For cleaning the inside of the cooling system and changing the coolant, see the following table.
Coolant
Interval for cleaning inside of cooling system and
changing coolant
Non-Amine Engine Coolant
(AF-NAC)
Every 2 years or every 4000 hours whichever
comes sooner
The coolant has the important function of preventing corrosion as well as preventing freezing.
Even in the areas where freezing is not an issue, the use of coolant is essential.
Komatsu machines are supplied with Non-Amine Engine Coolant (AF-NAC).
Non-Amine Engine Coolant (AF-NAC) has excellent anti-corrosion, antifreeze and cooling properties and can be
used continuously for 2 years or 4000 hours.
Komatsu recommends the use of Non-Amine Engine Coolant (AF-NAC).
If you use another coolant, it may cause serious problems, such as corrosion of the engine and aluminum parts
of the cooling system.
To maintain the anti-corrosion properties of Non-Amine Engine Coolant (AF-NAC), always keep the density of
Non-Amine Engine Coolant between 30 % and 64 %.
Non-Amine Engine Coolant (AF-NAC) is already diluted with distilled water. When using the coolant, investigate
the lowest temperature in the past and decide the density for the coolant from the coolant density table below.
When deciding the density for the coolant, set it for a temperature 10 °C below the actual lowest temperature in
the working area.
The coolant density varies according to the ambient temperature, but it must be over 30 % at least.
Coolant density table
Min. atmospheric tem-
perature
°C
-10 or
more
-15 -20 -25 -30 -35 -40 -45 -50
Density ( %) 30 36 41 46 50 54 58 61 64
MAINTENANCE PROCEDURE MAINTENANCE
4-20