Thermostat

Check the valve opening temperature.
Valve opening temperature 82 °C (177 °F)
Full opening temperature 95 °C (205 °F)
If the valve opening temperature is not as specified, replace the thermostat.

Check the valve lift.
Valve lift Min. 10 mm (0.4 in.) at 95 °C (205 °F)
If the valve lift is not as specified, replace the thermostat.