A thermostat that remains closed or only partially open
restricts the flow of coolant in the system.
A faulty thermostat may cause the engine to overheat.
A thermostat that sticks in the full open position prevents the engine
from reaching the normal operating temperature. Cold engine operation may
cause a buildup of excess carbon deposits on the following components:
- Remove the thermostat assembly.
Refer to
Engine Coolant Thermostat Replacement
.
- Suspend the thermostat
and a thermometer in water. Place the thermostat near the thermometer.
- Heat the water.
- Record the temperature at which the thermostat begins to open.
- Record the temperature at which the thermostat is open.
- Compare the temperature readings with the Engine Thermostats.
- Replace the thermostat and the gasket as needed.
Refer to
Engine Coolant Thermostat Replacement
.
- Fill the cooling system.
- Run the engine until the engine reaches normal operating temperature.
- Inspect for coolant leaks around the thermostat housing and the
gasket.
- Inspect the coolant level. Add additional coolant as necessary.
- Install the radiator cap.