We will encounter various vehicle problems while driving. The most typical one is that the vehicle water temperature is lower than normal while driving. What is the reason for this? Is it serious?
Many people only know the harm of engine overheating and do not pay special attention to engine undercooling. Some people even do not know what engine undercooling is. When the engine overheats, there is usually an alarm on the dashboard. In serious cases, it will even "boil", and the car will not be able to drive at this time. I believe anyone who has experienced it will have a deep memory; but the engine is too cold, which is different. Everything looks normal from the outside, there is no alarm on the dashboard, but the water temperature pointer points to a low position, and there is nothing abnormal when driving. There may be loud engine noise and high fuel consumption, but the car can drive normally. , so many people don’t care too much. But in fact, the impact of engine subcooling on the engine is considerable. A faulty thermostat causes the vehicle's water temperature to be low.
The thermostat is an important component in the cooling system because it determines the large circulation of the coolant when it is high and the small circulation of the coolant when it is low. When the vehicle is just started or the coolant temperature is low, the wax in the thermostat shrinks, the large circulation is closed, and the coolant circulates in the engine block. At this time, there is less circulating coolant, which helps the engine warm up quickly. When the coolant temperature rises to 85°C, the wax in the thermostat slowly melts and becomes larger in volume. It pushes the spring in the thermostat and opens the large circulation switch. At this time, the coolant flows into the radiator. Therefore, if the radiator is damaged and the large circulation is always turned on, the water temperature of the vehicle will become low.
During the small circulation of the cold zone liquid, the coolant only absorbs heat instead of forced heat dissipation. During the large circulation, the coolant quickly reduces the temperature of the coolant itself through the front radiator water tank; when the coolant water temperature is not high enough, Previously, the thermostat controlled the large circulation, and the coolant water channel circulated through the small pipe of the thermostat bypass valve.
After the water temperature is high enough, the paraffin in the thermostat will melt. When the wax melts into a liquid, it will hold up the switch, close the bypass valve, and open the main pipe. At this time, the coolant begins to circulate in a large way, and the water temperature exceeds the engine preset value. After the high temperature (85~95), the front water tank cooling fan starts to forcefully dissipate heat. Cooling fan total rotation
Cooling fan total rotation First check whether the water tank is short of antifreeze, causing high temperatures. If there is a lack of antifreeze, check whether there are leaks: water pumps and pipelines. Check whether water has entered the engine oil and the combustion condition of the spark plug. You can also determine whether antifreeze has leaked into the cylinder. Check whether there is air in the water circulation system causing poor circulation. Then check whether the surface of the water tank is too dirty, causing poor heat dissipation. Check whether there are water, alkali oxides, etc. in the water tank, causing poor circulation. Finally, check whether the temperature control switch is broken and is always powered on.