Diesel Data: Automotive Repair

Thermostat: Service and Repair

Thermostat

REMOVAL

1) Lift up the vehicle.
2) Remove the under cover.
3) Drain engine coolant.
4) Remove the radiator outlet hose from the radiator lower and the thermostat cover.





5) Remove the thermostat cover, and then remove the thermostat.





INSTALLATION

1) Install a gasket to thermostat.

NOTE:
Use a new gasket.

2) Install the thermostat and thermostat cover.

NOTE:
Install the parts with the jiggle pin facing the upside.

Tightening torque:
6.4 Nm (0.7 kgf-m, 4.7 ft-lb)





3) Install the radiator outlet hose to the radiator lower and the thermostat cover.





4) Install the under cover.
5) Lower the vehicle.
6) Fill engine coolant.

INSPECTION

1) Check that the thermostat does not have deformation, cracks or damage.
2) Check that the thermostat valve closes completely at an ambient temperature.
3) Immerse the thermostat and a thermometer in water. Raise water temperature gradually, and check the temperature and valve lift when the valve begins to open and when the valve is fully opened. Replace the thermostat if faulty.

NOTE:
^ During the test, agitate the water for even temperature distribution.
^ Leave the thermostat in the boiling water for five minutes or more before measuring the valve lift.
^ Hold the thermostat with a wire or the like to avoid contacting the container.

Starting temperature to open:
80 - 84°C (176 - 183°F)

Full open temperature:
95°C (203°F)

Total valve lift:
9.0 mm (0.354 in) or more