When Required; Clean Inside Of Cooling System - Komatsu D475A-5E0 Operation & Maintenance Manual

SERVICE PROCEDURE

WHEN REQUIRED

CLEAN INSIDE OF COOLING SYSTEM

Immediately after the engine is stopped, the coolant is at a high temperature and the radiator is under high internal pressure.
If the cap is removed to drain the coolant in this condition, there is a hazard of burns. Wait for the temperature to go down, then
turn the cap slowly to release the pressure before removing it.
Cleaning is performed with the engine running. When standing up or leaving the operator's seat, set the work equipment lock
lever and the parking brake lever to LOCK position.
For details of starting the engine, see "CHECK BEFORE STARTING ENGINE, ADJUST (PAGE 3-85)" and "STARTING ENGINE
(PAGE 3-114)" in OPERATION section.
Never approach the fan at the front of the machine while the engine is running.
There is danger of touching the fan.
Stop the machine on level ground when cleaning or changing the coolant.
Clean the inside of the cooling system, change the coolant according to the table below.
Coolant
Komatsu genuine
SUPERCOOLANT
(AF-NAC)
Komatsu genuine SUPERCOOLANT (AF-NAC) 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 SUPERCOOLANT (AF-NAC).
anticorrosion, antifreeze and cooling properties and can be used continuously for 2 years or 4000 hours. As a basic
rule, we do not recommend the use of any coolant other than SUPERCOOLANT (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 anticorrosion properties of coolant, always keep the density of coolant between 30% and 64%.
When selecting coolant, investigate the lowest temperature in the past and decide the density for the coolant from
the coolant density table below. When actually deciding the density for the coolant, set it approximately 10°C {18°
F} below lowest temperature. The density must be over 30% at least. If the density of obtained coolant is higher than
the necessary density for lowest temperature, dilute it with adequate distilled water, and then fill it into the tank.
If there is any unclear point, contact your Komatsu distributor.
Coolant density table
° C
Minimum Temp
° F
Density (%)
4 - 22
Interval for cleaning inside of cooling system
and changing antifreeze coolant
Every 2 years or every 4000 hours
whichever comes sooner
Above -10 -15 -20
Above 14 5 -4
30 36 41
WARNING
SUPERCOOLANT (AF-NAC) has excellent
-25 -30
-13 -22
46 50
MAINTENANCE
-35 -40 -45
-31 -40 -49
54 58 61
-50
-58
64