Thermostat Inspection

WARNING: This page is about a different car, the 2004 Suzuki Aerio and 2003 Suzuki Aerio. However, it is still accessible from the selected car via links, so may be relevant.

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 is free from foreign matters which would prevent valve from seating tight.
Check thermostat seal (2) for breakage, deterioration or any other damage.

Fig 1: Checking Thermostat Seal & Air Bleed Valve
Courtesy of SUZUKI OF AMERICA CORP.
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 overcooling or overheating tendency.

Fig 2: Checking Thermostatic Movement Of Wax Pellet

Courtesy of SUZUKI OF AMERICA CORP.