MAINTENANCE PROCEDURE 4.9.1.b 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 re- moving it. Cleaning is carried out with the engine running. When standing up or leaving the operator's seat, set the safety lock lever to the LOCK position. For details of starting the engine, see "3.3.1 BEFORE STARTING ENGINE" and "3.3.1.5 STARTING EN- GINE" in the "3.3 MACHINE OPERATIONS AND CONTROLS" section.
The engine is operated when washing, so it is dangerous if the machine moves when you are standing behind it. Never stand behind the machine when the engine is running. Oils, filters, coolants and batteries are considered special waste and must be collected and disposed of according to the regulations in force. Stop the machine on level ground when cleaning or changing the coolant. Clean the inside of the cooling system and change the coolant according to the indications given in the table. *: Permanent type antifreeze shall meet the requirements of ASTM D3306-03. Stop the machine on level ground when cleaning or changing the coolant.
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 ex- cellent anticorrosion, antifreeze and cooling properties and can be used continuously for 2 years or 4000 hours. Komatsu Supercoolant (AF-NAC) is strongly recommended wherever available. To maintain the anticorrosion properties of Supercoolant (AF-NAC), always keep the density of Supercoolant be- tween 30% and 68%.
When deciding the ratio of antifreeze to water, check the lowest temperature in the past, and decide from the mix- ing table given below. It is actually better to estimate and temperature about 10°C (18°F) lower when deciding the mixing ratio. The mixing ratio depends on the ambient temperature, but it should always be a minimum of 30% by volume (anti- freeze/total amount of coolant x 100). The freezing temperature of undiluted antifreeze is -15°C (5°F). Do not store undiluted antifreeze at a temperature of below -15°C (5°F).
Mixing rate of water and antifreeze 177 WARNING Kind of coolant Cleaning inside of cooling system and changing coolant Permanent type antifreeze (All season type)* Every year (autumn) or every 2000 hours whichever comes first Komatsu Supercoolant (AF-NAC) Every 2 years or after 4000 hours of operation Min. atomspheric temperature °C -10 -15 -20 -25 -30 Amount of antifreeze Liters 0.9 1.0 1.3 1.4 1.5 Amount of water Liters 2.1 2.0 1.7 1.6 1.5