Regular inspection
According to the data, the safety life of wax thermostat is generally 50000km
Thermostat switch status
Therefore, it is required to replace it regularly according to its safe life.
The inspection method of the thermostat is to debug the constant temperature heating equipment at the temperature and check the opening temperature, full opening temperature and lift of the main valve of the thermostat. If one of them does not meet the specified value, the thermostat shall be replaced. For example, for the thermostat of Santana JV engine, the opening temperature of the main valve is 87 ℃ plus or minus 2 ℃, the full opening temperature is 102 ℃ plus or minus 3 ℃, and the full opening lift is > 7mm.
Thermostat position
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Generally, the coolant of the water cooling system flows in from the engine block and out from the cylinder head. Most thermostats are arranged in the cylinder head outlet pipe. The advantages of this arrangement are simple structure and easy to eliminate bubbles in the water cooling system; Its disadvantage is that it will produce oscillation when the thermostat works.
For example, when starting a cold engine in winter, the thermostat valve is closed due to low coolant temperature. When the coolant circulates for a small time, the temperature rises quickly and the thermostat valve opens. At the same time, the low-temperature coolant in the radiator flows into the body, so that the coolant cools down again, and the thermostat valve is closed again. When the coolant temperature rises again, the thermostat valve opens again. The thermostat valve does not tend to be stable until the temperature of all coolant stabilizes and does not open and close repeatedly. The phenomenon that the thermostat valve opens and closes repeatedly in a short time is called thermostat oscillation. When this phenomenon occurs, it will increase the fuel consumption of the vehicle.
The thermostat can also be arranged in the water outlet pipeline of the radiator. This arrangement can reduce or eliminate the phenomenon of thermostat oscillation and accurately control the coolant temperature, but it has complex structure and high cost. It is mostly used for high-performance vehicles and vehicles that often drive at high speed in winter.
