Cooling System: Testing and Inspection
ON-VEHICLE INSPECTION
1. CHECK COOLING SYSTEM FOR LEAKS
CAUTION: Do not remove the radiator cap while the engine and radiator are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns.
a. Remove the radiator cap.
b. Fill the radiator with coolant and attach a radiator cap tester.
c. Warm up the engine.
d. Using the radiator cap tester, increase the pressure inside the radiator to 137 kPa (1.4 kgf/cm2, 19.9 psi), and check that the pressure does not decreases.
If the pressure decreases, check the hoses, radiator and water pump for leaks. If no external leaks are found, check the heater core, cylinder block and head.
e. Reinstall the radiator cap.
2. CHECK ENGINE COOLANT LEVEL AT RESERVOIR
a. Check that the engine coolant level is between the LOW and FULL lines when the engine is cold.
If the engine coolant is low, check for leaks and add "TOYOTA Super Long Life Coolant" to the FULL line.
If "TOYOTA Super Long Life Coolant" is not available, use a similar high quality ethylene glycol based non silicate, non-amino, non-nitrite and non-borate coolant with long-life hybrid organic acid technology. Do not substitute water for engine coolant.
3. CHECK ENGINE COOLANT QUALITY
a. Remove the radiator cap.
CAUTION: Do not remove the radiator cap while the engine and radiator are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns.
b. Check that there are no excessive deposits of rust or scale around the radiator cap and radiator filler hole.
If excessive rust or scale is present, clean as necessary.
c. Check that the coolant is free from oil contaminants.
If the coolant has oil contaminants, replace the coolant.
d. Reinstall the radiator cap.
INSPECTION
1. INSPECT RADIATOR CAP SUB-ASSEMBLY
NOTICE:
^ If the reservoir cap has contaminations, always rinse it with water.
^ Before using a radiator cap tester, wet the relief valve and pressure valve with engine coolant or water.
^ When performing steps (a) and (b) on the following page, keep the tester at an angle of over 30° above the horizontal.
a. Using a radiator cap tester, slowly pump the tester once every 3 seconds or more. Check that air is released from the vacuum valve.
NOTICE: Push the pump at a constant speed.
If air is not released from the vacuum valve, replace the reservoir cap.
b. Using a radiator cap tester, pump the tester once per second. Measure the relief valve opening pressure.
NOTICE: The pump speed above should be followed for the first pump only. It will close the vacuum valve. Once the vacuum valve is closed, the pump speed can be reduced.
Standard opening pressure: 93 to 123 kPa (0.95 to 1.25 kgf/cm2, 13.5 to 17.8 psi)
Minimum opening pressure: 78 kPa (0.8 kgf/cm2, 11.4 psi)
If the maximum value is less than the minimum opening pressure above, replace the reservoir cap.
HINT: Pay attention to the tester's maximum opening pressure value.