Cooling System: Testing and Inspection

ON-VEHICLE INSPECTION





1. INSPECT COOLING SYSTEM FOR LEAKS

CAUTION:
The hot engine coolant and steam will blow out from the radiator by thermal expansion themselves.
To avoid the danger of scalding yourself, do not remove the radiator cap while the engine and radiator are still hot.

a. Fill the radiator with a coolant water and attach a radiator cap tester.
b. Warm up the engine.
c. Pump it to 118 kPa (1.2 kgf/cm2, 17.1 psi), and check that the pressure does not drop.

HINT: If the pressure drops, check the hoses, radiator and water pump for leaks. If the coolant has not been leaked outside, check the heater core, cylinder block and cylinder head.

2. CHECK ENGINE COOLANT LEVEL AT RESERVOIR
a. The engine coolant should be between the "LOW" and "FULL" line.

HINT: If low, check for leaks and add "Toyota Long Life Coolant" or equivalent up to the "FULL" line.

3. CHECK ENGINE COOLANT QUALITY
a. Remove the radiator cap.

CAUTION: As the hot engine coolant and steam will blow out, do not remove the radiator cap while the engine and radiator are hot.

b. Check the radiator cap and the radiator filler hole for rust and dirt, the coolant should be free from oil.

HINT: If the coolant is excessively dirty, replace the coolant.

c. Reinstall the radiator cap.

4. INSPECT FINS BLOCKAGE





a. If fins are clogged, wash them with water or a steam cleaner. After the cleaning, dry the fins with compressed air.





NOTICE:
- If the distance between the steam cleaner and the core is too close, there is a possibility of damaging the fins, so keep the following injection distance.
- If the fins are bent, straighten them with a screwdriver or plier.
- Ensure that the electronic components are not ex posed to water.





5. INSPECT WATER PUMP ASSEMBLY
a. Visually check the air hole and water hole for coolant leakage.
If leakage is found, replace the water pump.
b. Turn the pulley seat, and check that the water pump bearing moves smoothly and does not make noise.
If necessary, replace the water pump.





6. INSPECT FLUID COUPLING ASSEMBLY
a. Check that the fluid coupling is not damaged and that no silicon oil leaks.
If necessary, replace the fluid coupling.
7. INSPECT WATER INLET W/ THERMOSTAT





HINT: The valve opening temperature is inscribed on the thermostat.





a. Immerse the thermostat in water and heat the water gradually.
b. Check the valve opening temperature of the thermostat.
Valve opening temperature: 80 - 84°C (176 - 183°F)
If the valve opening temperature is not as specified, replace the thermostat.





c. Check the valve lift.
Valve lift: 8 mm (0.31 inch) or more at 95°C (203°F)
If the valve lift is not as specified, replace the thermostat.
d. Check that the valve is fully closed when the thermostat is at low temperature (below 40°C (104°F)).
If not closed, replace the thermostat.





8. INSPECT RADIATOR CAP SUB-ASSEMBLY

NOTICE:
- If the reservoir cap has contaminations, rinse it with water.
- Before using a radiator cap tester, wet the relief valve and pressure valve with engine coolant or water.

a. Using a radiator cap tester, slowly pump the tester and check that air is coming from the vacuum valve.
Pump speed: 1 push per 3 seconds or more

NOTICE: Push the pump at a constant speed.

HINT:
- Pump speed: 1 push per 3 seconds or more
- If air is not coming from the vacuum valve, replace the reservoir cap.

b. Pump the tester and measure the relief valve opening pressure.
Standard opening pressure: 93 - 123 kPa (0.95 - 1.25 kgf/cm2, 13.5 - 17.8 psi)
Minimum opening pressure: 78 kPa (0.8 kgf/cm2, 11.4 psi)

NOTICE: The following pump speed is for the first time (in order to close the vacuum valve). After the first pumping, the pump speed can be reduced.

HINT:
- Pump speed: 1 push within 1 second.
- The tester's maximum reading is the opening pressure value.
- If the opening pressure is less than minimum, replace the reservoir cap.