Thermostat¶

Removal of thermostat¶

1. Drain engine coolant. (See Replacement of engine coolant › Drainage of engine coolant)
2. Disconnect radiator hose from water inlet.
3. (3S-GTE) Disconnect oil dipstick guide from water inlet. (See Oil cooler (3S-GTE) › Removal of oil cooler, step 8)

4. Remove water inlet and thermostat.

   1. Remove the two nuts and water inlet from the water pump.

      

   2. Remove the thermostat.

   3. Remove the gasket from the thermostat.

Inspection of thermostat¶

Inspect thermostat¶

1. Immerse the thermostat in water and gradually heat the water.

   

2. Check the valve opening temperature.

   Valve opening temperature: 80 – 84°C (176 – 183°F)

   If the valve opening temperature is not as specified, replace the thermostat.

3. Check the valve lift.

   Valve lift: 8 mm (0.31 in.) or more at 95°C (203°F)

   If the valve lift is less than specification, replace the thermostat.

   

4. Check that the valve spring is tight when the thermostat is fully closed.

   If necessary, replace the thermostat.

Installation of thermostat¶

1. Place thermostat in water pump.

   1. Install a new gasket to the thermostat.

   2. Align the jiggle valve of the thermostat with the upper side of the stud bolt, and insert the thermostat in the water pump.

      

      Hint

      The jiggle valve may be set within 5° of either side of the prescribed position.

2. Install water inlet.

   Install the water inlet with the two nuts.

   Torque:

   • 3S-GTE – 80 kg-cm (69 in.-lb, 7.8 N·m)
   • 5S-FE – 90 kg-cm (78 in.-lb, 8.8 N·m)

   

3. (3S-GTE) Connect oil dipstick guide to water inlet. (See Oil cooler (3S-GTE) › Installation of oil cooler, step 4)

4. Connect radiator hose to water inlet.
5. Fill with engine coolant. (See Replacement of engine coolant › Refill of engine coolant)
6. Start engine and check for leaks.