Cooling System Maintenance Coolant Recommendation The engine cooling system is provided with a mixture of 50% ethylene glycol anti-freeze and 50% water (For the vehicles of tropical area, the engine cooling system is provided with a mixture of 40% ethylene glycol anti-freeze and 60% water at the time of manufacture.) Since the cylinder head and water pump body are made of aluminum alloy casting, be sure to use a 30 to 60% ethylene glycol antifreeze coolant to assure corrosion protection and freezing prevention. Antifreeze DOOSAN recommends selecting automotive antifreeze suitable for gasoline engines using aluminum alloy parts. The antifreeze should meet ASTM-D3306 standard.
Check Coolant Level The items below are a general guideline for system checks. Refer to the engine manufacturer’s specific recommendations for proper procedures. Engine must be off and cold. If the concentration of the antifreeze is below 30%, the anticorrosion property will be adversely affected. In addition, if the concentration is above 60%, both the antifreeze and engine cooling properties will decrease, adversely affecting the engine. For these reasons, be sure to maintain the concentration level within the specified range. Never remove the pressure cap on a hot engine. The coolant level should be equal to the “COLD” mark on the coolant recovery tank.
Add approve coolant to the specified level if the system is low. Inspect Coolant Hoses Visually inspect coolant hoses and clamps. Remember to check the two coolant lines that connect to the pressure regulator/converter. Replace any hose that shows signs of leakage, swelling, cracking, abrasion or deterioration. Coolant Water Hard water, or water with high levels of calcium and magnesium ions, encourages the formation of insoluble chemical compounds by combining with cooling system additives such as silicates and phosphates. The tendency of silicates and phosphates to precipitate out-of-solution increases with increasing water hardness.
Hard water, or water with high levels of calcium and magnesium ions encourages the formation of insoluble chemicals, especially after a number of heating and cooling cycles. DOOSAN prefers the use of distilled water or deionized water to reduce the potential and severity of chemical insolubility. ppm = parts per million G643(E) Service Manual Chapter 2. Recommended Maintenance 21 CAUTION WARNING—PROPER USE Acceptable Water Water Content Limits (ppm) Chlorides (CI) 40 maximum Sulfates (SO4) 50 maximum Total Hardness 80mg/ℓ maximum Total Solids 250 maximum pH 6.0 ~ 8.0