24. SERVICE PROCEDURE Use city water for the cooling water. If river water, well water or other such water supply must be used, contact your Komatsu distributor. We recommend use of an antifreeze density gauge to control the mixing proportions. 1. Remove the radiator cap. 2. Close shutoff valve a at coolant filter. 3. Remove and discard the coolant filter b . Clean the gasket surface. 4. Apply a light film of lubricating oil to the gasket sealing surface before installing the coolant filter. NOTICE: Mechanical over-tightening may distort the threads or damage the filter head. 5. Install the filter. 6. Open the shutoff valve and install the radiator cap.
GENERAL The radiator cap seals the coolant filler opening of the radiator. Positive sealing requires a cap gasket and its contacting surfaces to be in good condition and a properly tightened cap. The radiator cap incorporates a pressure relief valve. The pressure relief valve keeps the pressure of the coolant at approximately 34 to 64 kPa or 0.35 to 0.65 kg/cm 2 (5 to 9 PSI). NOTICE: Operating the machine without a radiator cap, or with a cap without a relief valve set to operate at the correct pressure, can cause damage. PC450-ENG 3-27 WARNING Antifreeze is flammable, so keep it away from any flame. WWAARRNNIINNGG When removing drain plug, avoid pouring coolant on yourself.
24.1.3 CHANGING COOLANT FILTER WARNING Hot, scalding coolant can spray out if the radiator cap is re- moved suddenly. Relieve system pressure by slowly turning the cap to the first notch or lifting the safety lever (if equipped). Remove the cap only after the pressure is relieved. Hot, scalding coolant can spray out if the radiator cap is re- moved suddenly. Relieve system pressure by slowly turning the cap to the first notch or lifting the safety lever (if equipped). Remove the cap only after the pressure is relieved.