SEBU9064 39 Refill Capacities Fluid Recommendations Many engine failures are related to the cooling system. The following problems are related to cooling system failures: Overheating, leakage of the water pump and plugged radiators or heat exchangers. Corrosion Formation of mineral deposits These failures can be avoided with correct cooling system maintenance. Cooling system maintenance is as important as maintenance of the fuel system and the lubrication system. Quality of the coolant is as important as the quality of the fuel and the lubricating oil. Rust Scale Foaming of the coolant Many additives are depleted during engine operation. These additives must be replaced periodically.
Coolant is normally composed of three elements: Water, additives and glycol. Additives must be added at the correct concentration. Over concentration of additives can cause the inhibitors to drop out-of-solution. The deposits can enable the following problems to occur: Water Water is used in the cooling system in order to transfer heat. Formation of gel compounds Distilled water or deionized water is recommended for use in engine cooling systems. Reduction of heat transfer DO NOT use the following types of water in cooling systems: Hard water, softened water that has been conditioned with salt and sea water.
Leakage of the water pump seal Plugging of radiators, coolers, and small passages If distilled water or deionized water is not available, use water with the properties that are listed in Table 16 . Table 16 Glycol Glycol in the coolant helps to provide protection against the following conditions: Boiling Freezing Cavitation of the water pump For optimum performance, Perkins recommends a 1:1 mixture of a water/glycol solution. Note: Use a mixture that will provide protection against the lowest ambient temperature. Note: 100 percent pure glycol will freeze at a temperature of −23 °C (−9 °F). For a water analysis, consult one of the following sources:
Local water utility company Most conventional antifreezes use ethylene glycol. Propylene glycol may also be used. In a 1:1 mixture with water, ethylene and propylene glycol provide similar protection against freezing and boiling. Refer to Table 17 and refer to table 18 . Table 17 Agricultural agent Independent laboratory Additives Additives help to protect the metal surfaces of the cooling system. A lack of coolant additives or insufficient amounts of additives enable the following conditions to occur:
Acceptable Water Property Maximum Limit Chloride (Cl) 40 mg/L Sulfate (SO) 4 100 mg/L Total Hardness 170 mg/L Total Solids 340 mg/L Acidity pH of 5.5 to 9.0 Ethylene Glycol Concentration Freeze Protection 50 Percent −36 °C (−33 °F) 60 Percent −51 °C (−60 °F)