What are the reasons for the high water temperature in the car?

When some parts of the engine cooling system fail, it may cause the water temperature to rise, but the water temperature warning light may not turn on. In some cases, it may not reach the level of the alarm, so many car owners will ignore this problem.
Then, the reason for the high water temperature, in addition to the lack of coolant and the need to add coolant in time, may also be caused by the following reasons:

one
Thermostat failure
The thermostat responsible for switching the large/small cycle will choose to open or close the inlet of the coolant into the large cycle according to the change in temperature. If the thermostat is stuck, the movement is limited, and the large circulation inlet cannot be fully opened, resulting in less coolant flowing to the radiator, insufficient cooling of the coolant, and the engine temperature will naturally rise.

two
Cylinder head gasket damage
When the cylinder head gasket is structurally damaged and the sealing performance is reduced, the high-temperature exhaust gas in the combustion chamber may jump to the vicinity of the coolant passage. When the coolant comes into contact with the high-temperature combustion exhaust gas, it will further absorb heat, and its own temperature will rise significantly. The high-temperature coolant will disturb the overall working state of the cooling system, so that some engine components cannot be effectively dissipated.

three
Pump failure
The water pump is responsible for delivering coolant to various parts of the engine to dissipate heat from the engine. If the water pump is rusted, scale accumulation, etc., it will lead to low work efficiency, the engine will have poor heat dissipation, and the temperature will rise.