Coolant is a mixture of antifreeze and water that flows through your engine just like the blood in your body protecting the heart of your car from overheating. Its primary job is to absorb and transfer heat generated by the engine to the radiator where it is thrown away before the coolant returns to the engine. This process repeats over and over again while the engine is running to keep its optimal operating temperature for maximum performance, low emissions, and smooth operation.

The coolant also helps to heat your car’s interior running through a small version of a main radiator located under your dashboard. It is known as a heater and this is where warm air comes from. The coolant warms up the heater core which in turn gives its heat to the air that flows through it thanks to your blower fan.

In addition to its primary function, the coolant serves another important purpose. It contains alcohol that protects the engine against freezing at below zero temperatures. Besides, thanks to special additives in the coolant it protects the inside of the engine from rusting and mineral deposits forming.

Signs of bad coolant

Here are some tips that will help you find out when your coolant needs a replacement.

The coolant is dark, full of debris or smells bad

Fresh coolant is usually green, red, orange or some other color, so it shouldn’t be dark and murky as well as smell bad.

It is also a good idea to get a coolant flush instead of just a change if it is too dirty or smells too bad. 

The temperature gauge provides high readings 

If you notice that your engine is running hotter than normal you may have the coolant depleted. If this happens stop the car and wait until the coolant becomes colder and then check its level. Your coolant may be too old or it’s time to inspect your cooling system for leaks.

Blocked coolant hoses and passages may also be the case, so get in touch with your mechanic and have the cooling system checked out.

The engine overheats 

If your temperature gauge hits the red zone, you should immediately stop the car and shut off the engine to avoid serious damage to the motor.

The root of this problem may be low-quality coolant or some mechanical issues. In this case the vehicle must be towed to your mechanic for a repair.

Keep your engine coolant fresh

As the coolant ages, it becomes more and more acidic as well as loses its ability to absorb heat and prevent rust and corrosion. Such coolant needs to be replaced as soon as possible because this will lead to the buildup of gunk inside the cooling system and the engine. This may cause cooling system damage or its total failure. 

Worn-out coolant is also not able to safeguard your engine from freezing and boiling. This may become a real problem in hot summer or cold winter and lead to costly repairs.

How often should I replace coolant?

Follow the manufacturer’s recommendations found in your owner’s manual. In case you’re not satisfied with its quality and look, replace it even if it hasn’t served you the recommended time.