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Thermostat: Testing and Inspection

THERMOSTAT INSPECTION - L81

NOTICE: Use extreme care and do not damage or scratch the machined aluminum surfaces. Coolant leaks will result.





1. Check the valve opening temperature. Suspend the thermostat in glycol solution. Gradually heat the water until the thermostat begins to open. Check the temperature immediately after the thermostat opens. Replace the thermostat if it does not open within specifications. Starts to open temperature:
New: 84 - 88 degrees C (183 - 190 degrees F)
Used: 83 - 89 degrees C (181 - 192 degrees F)
2. Verify thermostat completely closes.
3. Inspect thermostat sealing surfaces for leaks.