Automobile coolant is the key liquid to ensure the normal operation of the engine, and has the function of anti-freezing, anti-boiling, anti-rust and anti-corrosion. Regular coolant replacement can effectively extend engine life and avoid failure due to overheating or icing. This article will explain the detailed steps and precautions for the correct discharge and replacement of coolant.

Preparatory work

1. Tools and materials

- New coolant (should comply with the model specified in the vehicle manual, do not mix different colors or composition of coolant)

- Distilled or deionized water (for flushing the system to avoid scaling)

- Protective gloves, goggles (coolant is toxic, avoid direct contact with skin and eyes)

- Catch basin (to collect old coolant)

- Wrench or socket (for removing drain plug or tank bottom cover)

- Funnel, towel or rag

2. Safety instructions

- The engine must be completely cooled before operation to avoid hot liquid splash burns.

- Old coolant should be properly recycled and not directly poured into the drain or soil (polluting the environment).

Drain old coolant

1. Locate the outlet

- Open the engine hatch and locate the drain plug or drain valve on the bottom of the tank (radiator). Some models may require removal of the hose under the tank.

- If the emission is difficult, refer to the vehicle maintenance manual to confirm the specific location.

2. Discharge old liquid

- Place the sink under the drain outlet and slowly unscrew the drain plug or release the hose clamp to allow the old coolant to flow into the sink.

- Open the tank cover and secondary tank cover (expansion pot) to accelerate liquid discharge.

- Wait for the liquid to drain completely, during which you can gently shake the vehicle or tap the tank to drain the remaining liquid.

Flushing cooling system

1. Flush the water tank and pipes

- Close the discharge outlet and fill the tank with distilled water or special detergent to full capacity.

- Start the engine, turn on the warm air to the highest temperature (make sure the coolant circulates to the whole car), and idle for 5-10 minutes.

- After extinguishing, drain the flushing solution again, repeat this step until the discharged liquid is clear and free of impurities.

2. Check the system tightness

- After flushing, check all pipes, clamps and pumps for leakage or aging, and replace parts if necessary.

Add new coolant

1. Correct ratio

- Choose coolant concentration according to local climate. Most coolants need to be diluted 1:1 with water (cold areas can increase the proportion of antifreeze).

- Use distilled water to avoid scale clogging the pipeline.

2. Filling procedure

- Close the discharge port and slowly pour the new coolant into the tank through the funnel until the level is close to the tank port.

- Start the engine and idle, while gently pinch the water pipe to discharge air bubbles, until the tank level drops and continue to refill.

- Ensure that the secondary tank (expansion pot) level is between "MAX" and "MIN".

Exhaust and inspection

1. Remove air

- Some models need to discharge air through special exhaust valves, or check the liquid level several times after driving and replenish it.

- If the temperature of the instrument panel is abnormally high, there may still be air that is not exhausted, and it needs to be re-vented.

2. Test and confirmation

- Road test for 10-15 minutes to observe whether the water temperature is normal.

- Check pipes, joints, and tank bottoms for leaks.

Matters needing attention

1. Coolant type

- Do not mix ethylene glycol (green/red) and propylene glycol (pink/blue). Mixing may cause chemical reactions to block pipes.

- The replacement cycle is generally 2-5 years or 40,000-80,000 km, refer to the vehicle manual for details.

2. Emergency handling

- If the coolant is insufficient, pure water can be added temporarily, but it needs to be replaced with the correct proportion of coolant as soon as possible.

Summary

Replacing the coolant is a work that requires careful operation, if you are not familiar with the steps, it is recommended to be handled by professional maintenance personnel. Regularly check the liquid level and color (if cloudy or discolored need to be replaced in advance), can effectively avoid engine overheating failure, to ensure driving safety.