FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Thermostat: Testing and Inspection

TESTING
Replace the thermostat if it is open at room temperature.
To test a closed thermostat:





1. Suspend the thermostat in a container of water as shown.
2. Heat the water and check the temperature with a thermometer. Check the temperature at which the thermostat first opens, and at which it is fully open.

CAUTION: Do not let the thermometer touch the bottom of the hot container.

3. Measure the lip 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)