Thermostat - Mechanical Test
Thermostat - Mechanical Test1. Remove the coolant thermostat.
2. Check the coolant thermostat for seating. Hold the coolant thermostat up to a lighted background. Leakage of light around the thermostat valve at room temperature indicates that the coolant thermostat should be replaced. Some coolant thermostats have a small leakage notch at one location on the perimeter of the thermostat valve, which is considered normal.
3. Immerse the coolant thermostat in a boiling antifreeze and water mixture.
4. See the General Specifications chart for coolant thermostat opening temperatures. Thermostat - Coolant