How do you add antifreeze to an engine properly?

Using antifreeze properly is crucial for maintaining an engine’s cooling system, particularly to prevent freezing in colder temperatures and to provide effective heat transfer.

Mixing antifreeze with a small amount of water is important because concentrated antifreeze can actually be less effective than a mixture. The typical recommendation for most antifreezes is to use a 50/50 mixture of antifreeze and water, which provides optimal protection against freezing and helps prevent overheating. This mixture also lowers the boiling point of the coolant and raises its freezing point, which is beneficial under various operating conditions.

Some might think that pouring antifreeze directly into the radiator—or using it straight from the container—could be sufficient, but doing so can lead to imbalances in the cooling system. Furthermore, if the engine is hot, adding antifreeze could cause damage due to the sudden temperature variation and the risk of steam burns from escaping vapor. Therefore, ensuring proper mixing and proportions is essential for effective engine cooling system performance.