COOLING SYSTEM


  1. OUTLINE


    1. The cooling system is a pressurized, forced-circulation type.

    2. TOYOTA genuine Super Long Life Coolant (SLLC) is used.

    3. A cooling fan control system in which the ECM optimally controls cooling fan speed is used. For details, refer to 8AR-FTS Engine Control.

    4. 3 thermostats are used to enhance cooling and warm-up performance.

      Thermostat Installation Position Objective
      Thermostat Water Inlet Controls the engine coolant flow rate from the radiator.
      Thermostat (Cylinder Block Side) Cylinder Block Sub-assembly Controls the engine coolant flow rate to the cylinder block sub-assembly during warm-up to shorten the time required to warm-up the engine and achieve low fuel consumption.
      Manifold Thermostat Water Hose of Throttle Body with Motor Assembly Reduces the engine coolant flow rate to the throttle body with motor assembly when the coolant temperature is high to suppress increases in intake air temperature.

    5. A direct coolant path to the cylinder head sub-assembly and cylinder block sub-assembly is provided in the engine side module (water inlet housing) and the distribution of engine coolant is optimized to prevent extreme increases in the temperature around the combustion chambers of the cylinder head sub-assembly and cylinder block sub-assembly when the thermostat (cylinder block side) installed in the cylinder block sub-assembly is closed.

    6. A bleeder valve is provided in the No. 3 water by-pass pipe and water hose sub-assembly to shorten the work time required when replacing engine coolant.

  2. SPECIFICATION


    1. Engine Coolant


      1. TOYOTA genuine Super Long Life Coolant (SLLC) is used. The maintenance interval is as shown in the table below:

        Coolant Type TOYOTA Genuine SLLC or the Following
        Maintenance Intervals First Time 160000 km (100000 miles)
        Subsequent Every 80000 km (50000 miles)
        Color Pink

        Tech Tips

        Similar high quality ethylene glycol based non-silicate, non-amine, non-nitrite, and non borate coolant with long-life hybrid organic acid technology (coolant with long-life hybrid organic acid technology consists of a combination of low phosphates and organic acids). Do not use plain water alone.

      2. SLLC is pre-mixed (50% coolant and 50% deionized water), and therefore does not need to be diluted.

      3. If LLC (red-colored) is mixed with SLLC (pink-colored), the interval for LLC (every 40000 km (24000 miles) or 24 months whichever comes first) should be used.

    2. Thermostat

      Thermostat Thermostat Opening Temperature Thermostat Closing Temperature
      Thermostat 82°C (180°F) -
      Thermostat (Cylinder Block Side) 78°C (172°F) -
      Manifold Thermostat - 83°C (181°F)