Cooling Fan: Thermostat: Inspection

INSPECT THERMOSTAT
HINT:

The valve opening temperature is stamped on the thermostat.

Fig 1: Identifying Valve Opening Temperature On Thermostat
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
1. Immerse the thermostat in water and gradually heat the water.
  
  Fig 2: Immersing Thermostat In Water
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
2. Check the valve opening temperature.
  Valve opening temperature: 80 to 84°C (176 to 183°F)
  
  If the valve opening temperature is not as specified, replace the thermostat.
3. Check the valve lift.
  Valve lift: 10 mm (0.39 in.) or more at 95°C (203°F)
  
  If the valve lift is not as specified, replace the thermostat.
  
  Fig 3: Checking Valve Lift
  Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
4. Check that the valve is fully closed when the thermostat is at a low temperature like 40°C (104°F).
If not closed, replace the thermostat.