求翻译：一般情况下，专用卡车在冬夏换季时应清洗保养一次，正常行驶中每6个月至8个月清洗保养一次，或者遇水温过高、漏水、开锅时清洗保养一次。清除导致发动机过热的痕迹和水垢，防止有害的腐蚀发生，避免并制止密封件和水箱的渗漏，彻底更换旧的冷却液。是什么意思？

Under normal circumstances, special-purpose trucks should cleaning once in winter and summer season, in normal driving once in every 6 to 8 months cleaning and maintenance, or when water temperature is too high, leakage, a: cleaning and maintenance. Clear traces of lead to overheating of the engine and boiler scale, prevent harmful corrosion occurs, avoid and stem the leakage of seal and water tanks, completely replaced the old coolant.