Remove and Test the Thermostat
Step 1Turn off the engine and allow the engine to cool.
Step 2Remove the bolts holding the thermostat cap in place.
Step 3Lift off the housing cap to expose the thermostat. Pull the thermostat out of the housing with your fingers. Take careful note of which way it sits so that you can reinstall it or its replacement in the same position.
Step 4Put the thermostat in a pan of water on the stove, and turn the burner on high.
Step 5Monitor the water temperature with an oven thermometer. The thermostat should open at about 195 degrees F if it is functioning properly.
Step 6Replace a faulty thermostat. Reinstall it if it opens and closes properly, and look for another problem in the cooling system.
Or with the use of an infrared thermometer
Friday, January 1st, 2010 AT 10:06 PM