Thermostat: Testing and Inspection

DIAGNOSIS AND TESTING





1. Remove the thermostat.
2. Suspend the thermostat in a container of water.

CAUTION: Never use a welding torch or soldering torch as the sudden introduction of heat alters the structure of the metal!

3. Heat the container and thermostat.

Note: The rate of increase should not be more than 1 - 2 °C/min (1.8 - 3.6 °F/min) from about 8 °C (14.4 °F) below the start of opening of the coolant thermostat.

4. Measure the temperature of the water.
5. Heat water to the fully open temperature of the thermostat and then measure the stroke.
6. If the specifications are not achieved, install a new coolant thermostat.