Thermostat check
As the engine warms up, the thermostat opens a large circulation circuit. If this does not happen, the engine will overheat. In this case, the radiator remains cold.
1. Remove thermostat as follows.
Pic. 5.30. Thermostat check
2.Measure the size «A» (pic. 5.30) thermostat.
Pic. 5.31. Heating the thermostat in the tank
3. Lower the thermostat into the container so that it does not touch the walls of the container, and slowly heat the water (pic. 5.31). At a temperature of +85°C, the thermostat's bimetallic spring should begin to lengthen. The spring reaches its maximum length at a temperature of +94°C. As soon as the water reaches the opening temperature, the control damper should begin to open.
4. Bring the water to a boil, then remove the thermostat and measure the size «b». Compare the value with the original «A», the difference should be 8 mm.
5. Check if the thermostat closes completely on cooling.
6. Replace thermostat.
Removal and installation of the thermostat
1. Disconnect a wire from the negative plug of the storage battery.
Attention! This deletes the codes entered into the memory devices, such as the radio code.
2. Drain the coolant as described earlier.
3. Remove the front top engine cover.
Pic. 5.32. Removing the thermostat: 1 - bolt; 2 – a cover of the case of the thermostat; 3, 7 - hose; 4 - thermostat; 5 - sealing ring; 6 - thermostat housing
4. After loosening the clamps, disconnect hoses 3 and 7 (pic. 5.32) cooling systems.
5. Turn away bolts 1 fastenings of a cover of the case of the thermostat and take out the thermostat 4.
Attention! Do not remove the thermostat from the cover on 4-cylinder and V6 engines, it may be damaged. Re-installation is not possible. If the thermostat is defective, it must be replaced along with the cover.
6. Before installing the thermostat, clean the gasket connections on the body and motor.
7. Establish a cover of the case of the thermostat with a new lining and wrap bolts 1 the moment of 10 Нм.
8. Connect hoses 3 and 7 of the cooling system. Pay attention to its correct fit and reliable tightening of the clamps.
9. Fill in coolant.
10. Connect a wire to the negative plug of the storage battery.
11. Warm up the engine to operating temperature and check that the radiator at the bottom is warm.
12. Check the tightness of the thermostat installation and hose connections.