Whenever you add engine coolant use equal parts of water and premium cooling system ethylene-glycol type coolant (antifreeze) that meets Toyota specifications. Do not use alcohol or methanol antifreeze, or mix them with specified coolant.
These vehicles have aluminum radiators and require a unique corrosion inhibited coolant formulation to avoid damage. Use only permanent type coolant that meets Toyota specifications. A coolant mixture of less than 40% engine coolant concentrate may result in engine corrosion and over-heating.
The factory installed solution of cooling system fluid and water will protect your vehicle to -35°F (-37°C). Check the freezing protection rating of the coolant at least once a year, just before winter.
Maintain a protection rating consistent with the lowest temperature in which you operate your vehicle or at least -20°F (-29°C) to prevent engine damage as a result of freezing and to ensure proper engine operating temperature. Rust and corrosion inhibitors tend to deteriorate with time, changing the coolant every 4 years or 60,000 miles is recommended for proper protection of the cooling system.
The Toyota Motor Corporation does not authorize the use of the recycled engine coolant nor do they sanction the use of any machines or devices that recycle engine coolant. Recycled engine coolant is not equivalent to the factory fill OEM coolant. The quality of the engine coolant degenerates with use. Recycling used engine coolant is very difficult to do without exposing the used coolant to additional foreign substances. Merely adding an additive to the coolant will not restore it. Always use new engine coolant that meets the Toyota coolant specifications for the engine being serviced.
The disposal of all used engine coolant must always be done in accordance with all applicable Federal, State and Local laws and regulations.
Dealing with the cooling system can be a dangerous matter unless the proper precautions are observed. It is best to check the coolant level in the radiator when the engine is cold. This is done by removing the radiator cap, on models without an expansion tank, and seeing that the coolant is within 2 inch (50 mm) of the bottom of the filler neck. On models with an expansion tank, if coolant visible above the MIN mark on the tank, the level is satisfactory. Always be certain that the filler caps on both the radiator and the reservoir are tightly closed.
In the event that the coolant level must be checked when the engine is warm on engines without the expansion tank, place a thick rag over the radiator cap and slowly turn the cap counterclockwise until it reaches the first detent. Allow all the hot steam to escape. This will allow the pressure in the system to drop gradually, preventing an explosion of hot coolant. When the hissing noise stops, remove the cap the rest of the way.
If the coolant level is low, add equal amounts of ethylene glycol based antifreeze and clean water. On models without an expansion tank, add coolant through the radiator filler neck. Fill the expansion tank to the MAX level on cars with that system.
Never add cold coolant to a hot engine unless the engine is running, to avoid cracking the engine block.
The radiator hoses and clamps and the radiator cap should be checked at the same time as the coolant level. Hoses which are brittle, cracked, or swollen should be replaced. Clamps should be checked for tightness (screwdriver tight only. Do not allow the clamp to cut into the hose or crush the fitting). The radiator cap gasket should be checked for any obvious tears, cracks or swelling, or any signs of incorrect seating in the radiator neck.
The cooling fan motor is controlled by a temperature switch. The fan may come on and run when the engine is off. It will continue to run until the correct temperature is reached. Take care not to get your fingers, etc. caught in the fan blades.
Never remove the radiator cap under any circumstances when the engine is operating. Before removing the cap, switch OFF the engine and wait until it has cooled. Even then, use extreme care when removing the cap from a hot radiator. Wrap a thick cloth around the cap and turn it slowly to the first stop. Step back while the pressure is released from the cooling system. When you are sure all the pressure has been released, press down on the cap, still with a cloth, turn and remove it.
DRAIN & REFILL
When changing the coolant the cooling system should be drained, thoroughly flushed, and refilled. This should be done with the engine cold.
- Remove the radiator cap.
- There are usually two drain plugs in the cooling system; one at the bottom of the radiator and one at the rear of the driver's side of the engine. Both should be loosened to allow the coolant to drain.
- Turn on the heater inside the car to its hottest position. This ensures that the heater core is flushed out completely. Flush out the system thoroughly by refilling it with clean water through the radiator opening as it escapes from the two drain cocks. Continue until the water running out is clear. Be sure to clean out the coolant recovery tank as well if your car has one.
- If the system is badly contaminated with rust or scale, you can use a commercial flushing solution to clear it out. Follow the manufacturer's instructions. Some causes of rust are air in the system, caused by a leaky radiator cap or an insufficiently filled or leaking system; failure to change the coolant regularly; use of excessively hard or soft water; and failure to use a proper mix of antifreeze and water.
- When the system is clear, allow all the water to drain, then close the drain plugs. Fill the system through the radiator with a 50/50 mix of ethylene glycol type antifreeze and water.
- Start the engine and top off the radiator with the antifreeze and water mixture. If your car has a coolant recovery tank, fill it half full with the coolant mix.
- Replace the radiator and coolant tank caps, and check for leaks. When the engine has reached normal operating temperature, shut it OFF, allow it to cool, then top off the radiator or coolant tank as necessary.
FLUSHING & CLEANING THE SYSTEM
- Drain the radiator as outlined in this section. Then add water until the radiator is full.
- Reinstall the radiator cap to the pressure relief position by installing the cap to the fully installed position and then backing off to the first stop.
- Start and idle the engine until the upper radiator hose is warm.
- Immediately shut OFF engine. Cautiously drain the water by opening the drain cock.
- Repeat Steps 1-4 as many times as necessary until nearly clear water comes out of the radiator. Allow remaining water to drain and then close the petcock.
- Disconnect the overflow hose from the radiator filler neck nipple.
- Remove the coolant recovery reservoir from the fender apron and empty the fluid. Flush the reservoir with clean water, drain and install the reservoir and overflow hose and clamp to the radiator filler neck.
- Refill the coolant system as outlined in this section.
If the radiator has been removed, it is possible to back flush the system as follows:
- Back flush the radiator, Ensure the radiator cap is in position. Turn the radiator upside down. Position a high pressure water in the bottom hose location and backflush. The radiator internal pressure must not exceed 20 psi.
- Remove the thermostat housing and thermostat. Back flush the engine by positioning a high pressure hose into the engine through the thermostat location and back flush the engine.
If the radiator is showing signs of rust and wear, it may be a good idea to thoroughly clean and get the cooling fins free from debris, while the radiator is out of the vehicle. Then using a suitable high temperature rust proof engine paint, paint the radiator assembly.