How Do You Replace the Antifreeze in Your Car?

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Replacing a vehicle’s antifreeze involves draining the old fluid using the drain valve at the bottom of the radiator and replacing it with new antifreeze. The antifreeze mixture should be 50 percent coolant and 50 percent water.

When done properly, replacing a vehicle’s antifreeze should only take a few minutes. However, the car will need time to cool down before making sure enough coolant is running through the engine.

  1. Park the car
  2. Park the vehicle on a flat surface away from small animals and children. Antifreeze is deadly, so keep it away from animals and kids. Allow the engine to cool down.

  3. Prepare to drain the old fluid
  4. Place a large bucket or pan underneath the drain valve, which is located at the bottom of the radiator. The bucket should hold at least 2 gallons.

  5. Drain the fluid
  6. Open the drain valve and allow the liquid to flow into the bucket. Be sure to get the liquid in the bucket, not on the ground.

  7. Close the drain valve
  8. Close the drain valve when the liquid stops flowing. Remove the bucket and clearly label it for recycling.

  9. Refill the radiator
  10. Open the radiator cap and fill the radiator with water.

  11. Turn on the engine
  12. Turn the engine on and turn the heater on high. Allow the engine to run for about 10 minutes, and keep an eye on the temperature gauge. If the car begins running hot, turn it off immediately. After 10 minutes, allow the engine to cool.

  13. Drain the radiator
  14. Once again, drain the radiator. Be sure to use a bucket as the water may have traces of antifreeze in it.

  15. Refill
  16. Refill the radiator with a mixture of 50 percent antifreeze and 50 percent water. Fill it to the “Max” line on the coolant recovery reservoir.

  17. Start the engine
  18. Replace the radiator cap and start the engine with the heater on high to allow the coolant to run through the system. Be sure the temperature gauge remains in the normal range.