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.So what’s causing the hot water?Xiaobian asked an old master with 20 years of experience in truck maintenance, he once encountered the reasons for the high water temperature with Xiaobian about one by one.It is summarized as the following points:

1. 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.

2. The insufficient tightness of the cooling fan belt installed on the water tank leads to insufficient rotation speed of the fan and the water pump. The insufficient rotation speed of the fan leads to low cold air flow of the water tank, and the insufficient rotation speed of the water pump leads to 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.

3. In front of the water tank, there is a card friend with an insulation curtain. When the water temperature is rising, there is no attention to open the insulation curtain for ventilation and cooling.

4, radiator hose plug smaller pipe cross section, water cycle efficiency is lower, because the tank heat pipe blockage of the pipe cross section decreases 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 increases, cause the cistern drainage,The reduced amount of water after drainage causes the engine to overheat.

5. After the thermostat fails, the failure or functional attenuation of the thermostat after long-term use makes the valve opening smaller, resulting in slow or even interrupted water circulation, which leads to the excessive water temperature of the engine.

The test criteria for determining whether the thermostat is suitable for continued use are to heat the thermostat in water to check the temperature at which the valve is opened and the temperature at which it is fully opened 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.

6. Water pump failure. If the truck does not add antifreeze in cold weather, the water in the water pump is easy to freeze, resulting in the pump impeller can not rotate.When starting the vehicle, the belt forcibly drives the pump pulley to rotate, it is easy to cause damage to the pump impeller and the pump shell.

7. Fan clutch failure. Most trucks running on the road are equipped with fan clutch, regardless of whether they are domestic or imported engines.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.