How to Change Antifreeze in a BMW 525Iby Tara Kimball
When the coolant in your BMW 525I breaks down or debris builds up, you should drain the radiator and replace it with a fresh coolant blend. Create a blend of equal parts of distilled water and antifreeze to fill the radiator. Most auto parts stores will accept the used coolant for recycling, providing you an option for proper disposal. BMW recommends changing the coolant in your 525I at least once every two years.
Park the 525I on a level surface. Raise the hood and let the engine cool. Remove the radiator cap. Place a large drain pan beneath the radiator drain plug on the passenger side of the radiator.
Unscrew the radiator drain plug. The plug protrudes from the radiator enough that you can unscrew it by hand. Drain all of the coolant into the drain pan.
Tighten the drain plug by hand. Remove the drain pan from under the car. Fill the radiator with a 50-50 blend of antifreeze and distilled water.
Start the engine. Let it idle until the engine warms up. Add coolant to the radiator as needed when the level drops. Turn the engine off once it warms up, then let it cool. Top off the coolant in the radiator if needed.
Replace the radiator cap and close the hood.