 printable version
Thermostat
The thermostat controls the flow direction of the coolant. Responsive to temperature change with a spring element as the heat engine operates two valves which, depending on the temperature of the cooling fluid flow is directed entirely or partly by the corresponding circuit. 1. The circulation of the small loop (temperature up to +87 ?� C) - the thermostat is closed. The bypass valve directs coolant to the pump. From there the liquid is again supplied to the engine. This mode is used to quickly warm the engine. 2. Mixed mode (temperature 87 ... + 102 ?� C) - the thermostat opens. The fluid circulating in the small loop, partially passes through the radiator. 3. The circulation around a large circuit (temperature is +102 ?� C) - the thermostat is fully opened. All fluid passes through the radiator. Removal and check thermostat If the thermostat is stalled, it can lead to great damage in the engine. The liquid will boil and evaporate quickly. In this case, it is impossible to continue movement. Have the car towed to the repair site. Removal and installation of the thermostat - simple operation. By purchasing the new thermostat, do not forget the new pads, including the lining of the case. You will also need the capacity to drain fluids. Only remove the thermostat on a cold engine. Different models of thermostat housings differ by location.
1. Disconnect the negative battery terminal. 2. Merge cooling liquid, as previously described. 3. Remove the front upper engine cover. 4. Loosen the hose clamp, disconnect the radiator hose from the thermostat housing. 5. Remove the small surge tank hose (having loosened the collar).
| Fig. 4.47. Location of the thermostat: 1 - the thermostat; 2 - the coolant pump; 3 - chain tensioner; 4 - exhaust manifold
|
| Fig. 4.48. Coolant pump block with thermostat 1 - belt pulley flange; 2 - the pump housing; 3 - pump impeller; 4 - union radiator hose; 5 - the thermostat; 6 - thermostat; And - from the radiator; B - by the engine; C - to the engine
|
6. Remove the thermostat housing and remove together with it (Fig. 4.47). The thermostat is configured with the water pump (Fig. 4.48).
| Fig. 4.49. Check thermostat
|
7. Place the thermostat in a container of water (Fig. 4.49) and by slowly heating water, check the temperature rating. For already in operation thermostat permissible difference in temperature response within ?� 3 ?� C. 8. Make sure that during the cooling valve is fully closed. 9. malfunction, replace the thermostat. On the 4- and 6-cylinder engines thermostat has one-piece construction. 10. Before installing the thermostat clean the joints with a gasket on the body and the engine. 11. Set the thermostat housing and new gasket and tighten to 10 N ?� m. 12. Connect the radiator hose, pay attention to its proper seating and tightness of the clamp. 13. Fill the coolant. 14. Connect the cable to the negative terminal of the battery. 15. Warm up the engine and make sure the bottom of the radiator heats up. 16. Check the tightness of the thermostat.
| 
