Coolant: When and How to Change It

For the normal functioning of the engine’s cooling system, it is essential to use cooling liquid, also known as coolant.

As well as maintaining the ideal temperature in the engine, coolant prevents corrosion and increases fuel economy.

Find out what engine coolant is and how it works.


What is Coolant?

Coolant is responsible for maintaining the temperature of the car’s engine at optimum levels.

This liquid circulates through the engine block and cylinder head, transporting the heat out through hoses that lead to the vehicle’s radiator.

In the radiator, this liquid passes through coils, where its temperature is reduced by natural ventilation, and then returns to the engine at a lower temperature.


What is Engine Coolant Used For?

The main purpose of the coolant is to prevent the water in the radiator from freezing when temperatures are below freezing.

On the other hand, when temperatures are too high, the coolant prevents the engine from overheating.



Is there a Coolant Temperature Sensor?

Most modern vehicles have a coolant temperature sensor, which provides crucial information to the engine control system to ensure the ideal temperature.

It is usually located near the thermostat or in the engine block itself, where it can accurately measure the temperature of the coolant circulating through the system.

Based on the readings from this sensor, the engine control system can adjust the air-fuel mixture, ignition timing and other variables to ensure optimum engine performance.

Although similar, there are slight differences between coolant and antifreeze.


What is the Difference Between Coolant and Antifreeze?

Coolant is a fluid used to remove heat from a vehicle’s engine or other mechanical systems to prevent overheating. Antifreeze is an additive mixed into the coolant to prevent it from freezing at very low temperatures.


Should I Use Coolant or Water?

Since water evaporates at more than 100°C and freezes at less than 0°C, its use to cool the engine is not recommended. You should therefore use coolant in the vehicle’s engine.



What are the Benefits of Coolant?

As well as preventing the engine from overheating, the use of coolant brings benefits not only to the engine, but also to the overall performance of the vehicle.


1. Improves Engine Performance

The coolant allows the engine to work at the ideal temperature, which translates into better performance for the car.

In this way, it prevents corrosion and avoids breakdowns that occur as a result of exposure to extreme temperatures.


2. Improves Cooling Circuit Operation

The engine coolant allows the liquid to circulate well in the radiator, ensuring that the car’s cooling system works properly.


3. Helps Prevent Engine Corrosion

Many coolants contain additives that help protect the cooling system against corrosion.

These additives form a protective layer on the internal metal surfaces of the system, preventing the formation of corrosion that can damage the radiator, hoses and other parts of the system.


4. Fuel consumption savings

One of the ways to save fuel and reduce pollutant emissions is to get the car’s engine up to the ideal operating temperature as quickly as possible.


What Can Happen if you Don’t Change the Coolant?

If you don’t change the coolant regularly, several problems can arise that negatively affect the performance and durability of your vehicle, such as:

  • Accumulation of dirt and sediment that can clog the cooling system;
  • Internal corrosion, which can cause leaks and permanent damage to engine parts;
  • Damage to parts such as seals, gaskets and metal parts, which may result in the need to replace the engine;
  • Failure of the air conditioning system due to deterioration of the coolant;
  • Reduced cooling capacity, which can lead to an increase in engine temperature and the risk of overheating.



How do I Choose the Right Coolant for My Car?

You should first check the manufacturer’s specifications in the owner’s manual. Then identify what characteristics the product should have, depending on factors such as geographical location.

Also, remember that a good coolant should be less viscous so that it can be transmitted through the engine without any problems.

If possible, choose a product with anti-corrosion, anti-fouling and anti-cavitation properties to preserve all its components.


How do I Change the Coolant?

Before replacing your car’s coolant, make sure the engine is cold to avoid serious burns. Then open the hood of your vehicle and locate the radiator. It is usually at the front of the engine, behind the radiator grille. Once you have located it, you should:

  1. Find the drain screw at the bottom of the radiator;
  2. Insert the liquid collection container and open the screw;
  3. Drain the liquid carefully;
  4. Close the drain screw and fill the coolant tank with new product until it reaches the “MAX” mark;
  5. Start the engine and let it run for a few minutes to pump the new liquid through the system;
  6. Check for coolant leaks from the radiator or reservoir;
  7. Replace the radiator cap and close the hood.


What Tools Do I Need to Change the Coolant?

In addition to the coolant, you need:

  • Open Ended Wrench;
  • Drain pan;
  • Funnel, to facilitate the process of refilling the coolant after replacement.

It is also advisable to wear protective goggles and gloves to avoid possible toxic reactions.

To check the antifreeze, you can use the KROFtools Anti Freeze Test.



Click on the image to find out more about the Anti Freeze Tester (ref.8727).


When Should you Replace the Coolant?

If there are no indicators of anomalies in the cooling system, the ideal is to replace it every 2 years or 40,000km.


líquido ?

The price ranges from 8 euros to 40 euros, depending on the properties of the fluid and the model of the vehicle in question.

Looking to find out more about the automotive world? Then follow us on Facebook and keep up with all the content we share on a daily.


2 thoughts to “Coolant: When and How to Change It”

  1. My sister bought a car a couple of weeks ago, and she asked me if I knew anything about coolants and engine maintenance. I’m glad you elaborated on using coolants to prevent engine damage and expensive future repairs. My sister will be thankful for your advice on protecting her car parts from corrosion.

    1. Dear Eli Richardson,

      We appreciate your feedback, and are happy to help.

      Keep watching our post on KROFtools blog and if you have any doubt don´t hesitate in contacting us on our through our social media.

      KROFtools team

Leave a Reply

Your email address will not be published.