Thermostat Test

Replace the thermostat if it is open at room temperature.

To test a closed thermostat:

1. Suspend the thermostat (A) in a container of water. Do not let the thermometer (B) touch the bottom of the hot container.
   Fig 1: Suspending Thermostat In Container Of Water

   Courtesy of AMERICAN HONDA MOTOR CO., INC.
2. Heat the water and check the temperature with the thermometer. Check the temperature at which the thermostat first opens, and at which it is fully open.
3. Measure the lift height of the thermostat when it is fully open.

   Standard Thermostat 

   Lift Height: Above 10.0 mm (0.39 in.) 

   Starts Opening: 169-176°F (76-80°C) 

   Fully Open: 194°F (90°C)