发动机冷却系统所用的冷却水必须用清洁的软水。如果向冷却系加注井水、河水、泉水、海水等硬水，就很容易在水套内形成水垢，使传热散热效能降低，不能有效地维持发动机的正常温度，使发动机过热，动力性下降，油耗增加，加速机件的不正常磨损。1．硬水及其软化井水、泉水、河 The cooling water used in the engine cooling system must be clean, soft water. If the cooling system with well water, river water, spring water, sea water and other hard water, it is easy to form scale in the water jacket, so that heat transfer cooling efficiency, can not effectively maintain the normal engine temperature, the engine overheating, power decreased , Fuel consumption increases, accelerating parts of the abnormal wear and tear. 1. Hard water and its softened well water, spring water, river