Komatsu WA100M-7, Operation And Maintenance Manual

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5.2 Basic maintenance guidelines
Maintenance
5-12
WA80M-7, WA100M-7 – VENAM03001
Coolant
 The coolant has the important function of preventing corro-
sion and freezing.
 Komatsu machines are shipped with Komatsu Supercoolant
(AF-NAC). Komatsu Supercoolant (AF-NAC) has excellent
anti-corrosive, antifreeze and cooling properties and can be
used continuously for 2 years or 4000 hours.
 We recommend using Komatsu genuine Supercoolant (AF-
NAC) exclusively. Using any other coolant may cause serious
damage such as corrosion of the engine or of cooling system
components that use light metals like aluminium.
 When using Komatsu Supercoolant (AF-NAC) there is no
need to use anti-corrosive.
For details see “Cooling system – cleaning internal area of the
cooling system (5-32)”.
 Use distilled water or tap water (soft water) for diluting the
antifreeze coolant.
 Natural water, such as a river water or well water (hard water),
contains large amounts of minerals (calcium, magnesium,
etc.). This accelerates the formation of scale inside the
engine or the radiator. Once present, scale is very difficult to
remove. It also causes overheating due to poor heat
exchange. We recommend using water with an overall hard-
ness of less than 100 ppm to dilute the coolant.
 When using antifreeze, always observe the precautions given
in the Operation and Maintenance Manual.
 Antifreeze is flammable, so be extremely careful not to
expose it to flame or fire.
 The ratio of Supercoolant (AF-NAC) to water varies according
to the ambient temperature.
 Even in areas where no freezing temperatures occur, use
Supercoolant (AF-NAC) in a mixing ratio of at least 30% to
prevent corrosion of the cooling system.
 Supercoolant (AF-NAC) may be supplied already mixed. In
this case, do not dilute with water.
 If the engine overheats, wait for the engine to cool before add-
ing coolant.
 A low coolant level causes overheating and corrosion due to
air in the coolant.