Attention! The engine must be completely cool.
Examination
1. Measure the coolant level, check the tension of the drive belt and the operation of the temperature sensor.
2. If the engine takes too long to warm up, the thermostat is most likely stuck open. Replace thermostat.
3. If the engine is overheating, check the temperature of the upper radiator hose, if the hose is not hot, then the thermostat is stuck closed. Replace thermostat.
4. For a more thorough check, the thermostat must be removed from the engine.
5. If the thermostat does not close at room temperature, it is defective and must be replaced.
6. Dip the thermostat in a container of cold water (thermostat closed).
7. Heat the water in the container and monitor its temperature. The thermostat must not touch the walls and bottom of the container.
8. Record the thermometer reading when the thermostat is just starting to open and when it is fully open. Compare the obtained values with the technical requirements.
9. Replace the thermostat if it does not open or close or is stuck in any position.
Replacement
1. Disconnect the negative battery cable.
2. Drain the coolant from the radiator. On six-cylinder engines, remove the air intake pipe.
3. Disconnect the radiator hose (A) and unscrew the bolts from the thermostat cover (IN) – 4-cylinder models.
4. Remove the bolt (IN) coolant pipes. Disconnect the tube from the thermostat cover and unscrew the cover bolts (A) – 6-cylinder models.
5. Remove the thermostat cover.
6. Remove the thermostat.
7. Clean the mating surfaces and install a new gasket.
8. Installation is carried out in the reverse order of removal.