What causes the excessive water temperature?The engine water temperature is high for no more than these 7 reasons

Card friends know that we should always pay attention to the water temperature in the driving, the engine water temperature should be between 80°C~90°C under normal circumstances, if the water temperature is often higher than 95°C or boiling should check the fault.

High engine water temperature

So what’s causing the hot water?I asked an old man with 20 years of experience in truck maintenance, and he explained the reasons for the high water temperature he had ever encountered.Xiaobian is summarized as the following points:


The coolant in the water tank is below the lowest scale line, which is that the daily maintenance work is not in place, and the lack of coolant is not noticed.Add coolant to specified scale.


The tightness of the cooling fan belt installed on the water tank is not enough, and the speed of the fan and the water pump is not enough because of skidding. The insufficient speed of the fan leads to the low cold air flow of the water tank, and the insufficient speed of the water pump leads to the slow circulation speed of the coolant.


In front of the water tank equipped with insulation curtain card friends, when the water temperature is rising, did not pay attention to open the insulation curtain ventilation and cooling, this situation is often run north card friends in winter.


Made pipe cross section pipe plugging smaller water tanks, water cycle efficiency is lower, the engine into the water tank on the pipe in the water than the amount of water that drain into the engine as a result, the surplus of water in the tank after a cooling water pipe, make on the pipe pressure increased, cause cistern drainage, drainage is reduced after the engine is overheating.


Engine engine


Thermostat failure, thermostat failure or function attenuation after long-term use of the valve opening becomes smaller, resulting in slow or even interrupted water circulation, leading to the engine water temperature is too high.


The test criteria for determining whether the thermostat can continue to be used are to heat the thermostat in water, check the temperature at which the valve begins to open and the temperature at which it is fully open, and the lift of the valve from open to fully open.The temperature at which the valve begins to open is generally about 80°C, and the temperature at which it is fully opened is generally about 90°C. The lift of the valve is generally 7~10 mm.


Thermostat thermostat


The pump is out of order. If the truck does not add antifreeze in cold weather, the water in the pump is easy to freeze and the impeller of the pump cannot turn.When starting the vehicle, the belt forcibly drives the pump to rotate, and it is easy to cause damage to the pump.


Fan clutch failure. Most trucks on the road today, whether they are domestic or imported, are equipped with fan clutch.Fan clutch he can adjust the speed of the fan according to the temperature of the engine, so that the engine continues to work in the best working state.When the fan clutch failure, it is easy to cause excessive water temperature, water tank boiling.

Post time: May-17-2021