COOLING SYSTEM

OUTLINE

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

2. Toyota Genuine Super Long Life Coolant (SLLC) is used.

3. 2 thermostats are used to improve 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.

4. A direct coolant path is provided in the engine side module (water inlet housing) to the cylinder head sub-assembly and cylinder block sub-assembly 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.

5. A electric water pump assembly is used. For details of electric water pump assembly, see the HEATING / AIR CONDITIONING section.

SPECIFICATION

1. Engine Coolant

   Type		Toyota Genuine Super Long Life Coolant (SLLC) or 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 is a combination of low phosphates and organic acids). Do not use plain water alone.
   Color		Pink
   Maintenance Intervals	First Time	160000 km (100000 miles)
   	Subsequent	Every 80000 km (50000 miles)
   Coolant Concentration		50% Coolant and 50% Deionized Water

   Tech Tips

   SLLC is pre-mixed (50% coolant and 50% deionized water). Therefore, no dilution is needed when SLLC in the vehicle is added or replaced.

2. Thermostat

   Thermostat	Thermostat Opening Temperature
   Thermostat	82°C (180°F)
   Thermostat (Cylinder Block Side)	78°C (172°F)