1. Reason: The thermostat is stuck and won't open. Solution: You can try it off.
2. Reason: The water pump is broken. Solution: If there is no thermostat, start the engine directly and increase the throttle to see if the water in the water tank circulates. If it doesn't circulate, the water pump is broken.
3. Cause: The water tank is too dirty, which causes the water tank to be blocked. Solution: Clean the water tank.
The function of thermostat is to prevent the engine from supercooling. After the engine works normally, if there is no thermostat when driving in winter, the engine temperature may be too low. At this point, the engine needs to temporarily stop the water circulation to ensure that the engine temperature is not too low.
Extended data:
When the cooling temperature is lower than the specified value, the fine paraffin in the thermostat temperature sensor is solid, the thermostat valve closes the passage between the engine and the radiator under the action of the spring, and the cooling liquid returns to the engine through the water pump and circulates in the engine. When the temperature of the coolant reaches the specified value, paraffin wax begins to melt, gradually becomes liquid, the volume increases, and the rubber tube is compressed and shrunk.
When the rubber tube contracts, it generates upward thrust on the push rod, and the push rod generates downward reverse thrust on the valve to open the valve. At this time, the coolant returns to the engine through the radiator and thermostat valve, and then returns to the engine through the water pump for large circulation.
Thermostats are mostly arranged in the water outlet pipe of the cylinder head, which is simple in structure and easy to eliminate bubbles in the cooling system; The disadvantage is that the thermostat is often switched on and off when it works, resulting in oscillation.
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