The high water temperature may be caused by the following reasons: 1 The cooling fan does not rotate. The cooling fan can be controlled by a temperature control switch; It can also be controlled by a water temperature sensor. 2. Insufficient cooling medium ① antifreeze: high-end cars are required to be filled with antifreeze all year round; ② Water or distilled water: temporary substitute; ③ Water tank cover leaks. The thermostat is broken. (1) If you want to remove the thermostat, you should block the small circulation at this time to ensure that all the coolant is dispersed by the water tank; ② When installing a new thermostat, pay attention to the water hole. The water tank is blocked. ① Remove external blockage with water or air; ② Internal blockage will affect the circulation of coolant and generate pressure. At this time, there will be two results: first, the water tank leaks; Second, the water temperature is extremely high when driving at high speed. 5. Pump failure ① The timing belt is broken due to slipping or sticking of the impeller; ② Impeller deformation 6. Cylinder corrosion ① When flushing the combustion chamber and waterway, the drain pipe will drain water or discharge white smoke, resulting in frequent water shortage in the water tank; (2) Flush waterways and oil paths (oil with water is white); (3) The waterway is washed away, resulting in poor heat dissipation of the cylinder block, especially at high speed; ④ The waterway is blocked. 7. Incorrect ignition timing (corrected by timing light) and high oil pressure.