Escort L4-122 2.0L SOHC (1997)
Thermostat: Testing and Inspection
DESCRIPTION
Overheating or failure to reach normal operating temperature can indicate improper thermostat operation. Inspection and temperature-testing of the
thermostat will verify its condition.
INSPECTION
NOTE: Insufficient heat and failure of the engine to reach operating temperature can indicate low temperature leakage of the water thermostat.
Cool the thermostat to room temperature for this inspection.
1. Remove the thermostat.
2. Hold the thermostat against a lighted background and inspect for light between the valve and valve seat. If light is visible, replace the thermostat.
OPERATION
1. Suspend the thermostat and an accurate thermometer in a suitable container filled with water. Do not allow the test pieces to touch the bottom of
the container.
2. Heat the water until boiling while observing the thermometer temperature.
NOTE: "Fully open" means the water thermostat valve lifts a distance of 5.8 mm (0.23 in) or more off of the valve seat.
3. The water thermostat should begin to open at 86.7-90.6°C (188-195°F) and be fully open at 100°C (212°F).
4. Replace the thermostat if it does not operate as specified.
