Why is the antifreeze level decreasing?
2 Answers
Reasons for decreasing antifreeze level: 1. Normal evaporation: Under the continuous high temperature of the engine, some antifreeze will inevitably evaporate, but the amount is usually minimal; 2. Faulty leakage: Damage to the radiator gasket or loosening of the overflow tank, water pump joint surface, and pipe connections in the cooling system can lead to antifreeze leakage; 3. Antifreeze entering the cylinder and participating in combustion, such as due to cylinder cracks, gasket erosion, or corrosion deformation. In such cases, check the oil dipstick for any emulsification. Antifreeze, also known as coolant, is designed to prevent freezing, ensuring the cooling system remains operational during cold winter temperatures without freezing.
As an experienced driver who has owned several cars, coolant loss is quite common. Usually, it's a minor issue like aging hose cracks causing leaks, especially as plastic components become brittle over time; or the radiator cap isn't sealed properly, allowing some coolant to evaporate under high temperatures. Additionally, loose or corroded water pump connections can also lead to leaks, which can be confirmed by wet spots under the car after parking. A more serious concern is engine head gasket failure, where coolant may mix with engine oil or burn off, significantly increasing the risk of engine overheating and breakdown. When checking, inspect the min-max line with a cold engine. If the level keeps dropping, it's time to investigate—don't wait until it's completely empty. I recommend checking the coolant level every three months—keeping it stable is ideal. Minor issues can often be fixed with DIY part replacements, but delaying repairs can lead to costly engine damage.
