Thermostat Inspection
Reference: THERMOSTAT REMOVAL AND INSTALLATION
- Make sure that air bleed valve (1) of thermostat is clean.
Should this valve be clogged, engine would tend to overheat.
- Check to make sure that valve seat (2) is free from foreign matters which would prevent valve from seating tight.
- Check thermostat O-ring (3) for breakage, deterioration or any other damage.
- Check thermostatic movement of wax pellet as follows:
- Immerse thermostat (1) in water, and heat water gradually.
- Check that valve starts to open at specific temperature.
Temperature at which valve begins to open
80 - 84 °C (176 - 183 °F)
Temperature at which valve become fully open
95 - 97 °C (203 °F)
Valve lift
More than 8 mm at 95 °C (203 °F)
If valve starts to open at a temperature substantially below or above specific temperature, thermostat unit should be replaced with a new one. Such a unit, if reused, will bring about over cooling or overheating tendency.