. MAINTENANCE SERVICE PROCEDURE CLEAN INSIDE OF COOLING SYSTEM WARNING 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 antifreeze coolant is essential. Komatsu machines are supplied with Komatsu Supercoolant (AF-NAC). Komatsu Supercoolant (AF-NAC) has excellent 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 Komatsu genuine 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 Supercoolant (AF-NAC), always keep the density of Supercoolant between 30% and 68%. Supercoolant (AF-NAC) is already diluted with distilled water. When using coolant, investigate the lowest temperatures 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 for a temperature 10 ° C (18 ° F) lbelow the actual temperature. The coolant density varies according to the ambient temperature, but it must always be a minimum of 30%.
Coolant density table 4 - 27 Immed iately after t he engine is stoppe d, the engine c oolant is h ot and the pressure inside the sub-tank is high. Removing the cap an d draining t he water u nder this c ondition could cause bu rns. A llow the engine to cool down , then turn the cap slowly to relea se the pres sure. Start th e engine an d flush th e system. When standing up or leav ing the operator's s eat , se t the shift l ever to the N position and set the parking bra ke switch to the PA RKING position .
For det ails of start ing the e ngine, see "OPERATIONS , CHECKS BEFORE STARTING (PAGE 3-83)" and "STARTING ENGINE (PAGE 3-84)" in th e OPERATION sectio n of the Opera tion and M aintenanc e Manual When t he underco ver is removed, ther e is danger of t ouching th e fan. Never go to the fro nt of the machine w hen the engine is running Stop the machine o n level g round wh en cleaning or changi ng the coolant. Clean th e inside of the cooling syste m, change th e coolant accordin g to the table below.
Interva Antifreeze coolant l for cleaning inside of cooling system and changing antifreeze coolant Komatsu supercoolant Ev (AF-NAC) ery two years or every 4000 hours whichever comes first Minimum Temp °C Above - 10 -15 -20 -25 -30 -35 -40 -45 -50 °F Above 14 5 -4 -13 -22 -31 -40 -49 -58 Concentration (%) 30 36 41 46 50 54 58 61 64