Device and repair of Toyota RAV4 SUVs (Toyota RAV) - The thermostat-//

Toyota PAB4-Toyota RAV4
1. Operation of the car
2. Maintenance
3. Engines
4. Cooling systems and conditioning
   General information
   Specifications
   Service and repair of the cooling system
      Thermostat
      Radiator fan
      Radiator and broad tank
      Water pump
      Sensor of the index of temperature of cooling liquid
      Radiator fan thermoswitch
      Heater fan electric motor
      Knot of management of systems of heating and air conditioning
      Heater radiator
   Check and service of the air conditioning system
5. Fuel system and system of production of the fulfilled gases
6. System of ignition
7. The control system and decrease in toxicity of the fulfilled gases
8. Coupling
9. Transmission
10. Driveshaft and shaft of the drive of driving wheels
11. Brake system
12. Suspension bracket
13. Steering and running gear
14. Body
15. Electric equipment
Schemes of electric equipment


Toyota RAV4>> Cooling systems and conditioning>> Service and repair of the cooling system>> Thermostat
       PREVENTION
When opening a cover of a radiator on the hot engine be careful as the coming-out vapors can lead to severe burns. Close a radiator cover a thick layer of fabric and slowly turn off a cover to the hissing sound. After the hissing termination slowly turn off and uncover a radiator.

Check of the thermostat installed on the car
Before check of the thermostat check the level of cooling liquid, a tension of a belt of the drive of the water pump and operability of the sensor of temperature.
If after start of the cold engine it gets warm very long, perhaps, the thermostat is constantly open and cooling liquid circulates on a big circle. In this case replace the thermostat.
If the engine overheats, a hand check temperature of the lower hose of a radiator. If the hose cold, perhaps, the thermostat is constantly closed and cooling liquid constantly circulates on a small circle. In this case also replace the thermostat.
If the lower hose of a radiator hot, it demonstrates that the thermostat is open and cooling liquid passes through a radiator. In this case it is necessary to address on service station for search and elimination of the reason of an overheat of the engine.
Check with removal of the thermostat
Remove the thermostat.

Fig. 4.1. Thermostat: 1 – secondary spring; 2 – frame; 3 – valve; 4 – valve saddle; 5 – flange; 6 – plunger; 7 – adjusting pin; 8 – main spring


Appearance of the thermostat is shown in fig. 4.1 .

Fig. 4.2. Check of opening of the valve of the thermostat in a vessel with hot water


Previously it is possible to check operability of the thermostat so: suspend it on a thread in the glass vessel filled with water and heat water to boiling (fig. 4.2) . When boiling water the valve of the thermostat has to open. Otherwise replace it.
Temperature of opening of the valve of the thermostat is written on its case.
The thermostat which valve is not closed when cooling water is also faulty and is subject to replacement.
Replacement of the thermostat
Switch off ignition and disconnect a wire of "weight" from the rechargeable battery.
Merge cooling liquid from a radiator. Disconnect a radiator hose from a thermostat casing.

Fig. 4.3. Otvorachivaniye of nuts of fastening of a casing of the thermostat on release cars till 2001


On release cars till 2001 remove a thermostat casing from a back part of the case of the water pump (fig. 4.3) . For simplification of access to the lower nut of fastening of a casing of the thermostat it is recommended to remove an oil filter.

Fig. 4.4. An arrangement of nuts of fastening of a casing of the thermostat on release cars since 2001


On release cars since 2001 remove the generator and turn off nuts of fastening of a casing of the thermostat (fig. 4.4) .
Remove the thermostat, having remembered situation in which it was installed.
Install a new sealing ring on the thermostat and clear privalochny surfaces of a casing of the thermostat.
On release cars till 2001 install the thermostat in a thermostat casing. Then establish a casing with the thermostat in a back part of the water pump so that the adjusting pin settled down from above.

Fig. 4.5. At installation of the thermostat, the adjusting pin has to settle down from above


On release cars since 2001 install the thermostat in a nest of the block of cylinders so that the adjusting pin settled down from above (fig. 4.5) .
Fix by nuts a casing of the thermostat and establish other elements removed earlier.
Fill in cooling liquid.
Start the engine and be convinced of lack of leaks.