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When Is It Recommended To Use Coolant?

While most of us are aware that vehicles use something called coolant, many of us are unsure as to exactly what coolant is or why our cars need it. Coolant, also known as anti-freeze, is used in the cooling systems of most cars to help maintain the vehicle’s engine temperature within the normal operating range. However, that is not the only purpose of engine coolant. In fact, it is recommended to always use coolant because it helps prevent rust and mineral build-up from forming in your car’s radiator. Since there is always water present in your car’s radiator, it is always wise to have coolant in the system so that your car remains protected against corrosion year-round.

The name coolant can sometimes be confusing because we associate the word “coolant” with something that would only be needed during the warm summer months. However, coolant also provides protection in the cold winter months by making it unlikely for the water in your car’s radiator to freeze. This is why the additive is also known as anti-freeze. In general, most vehicle manufacturers recommend that vehicles should not be used without coolant because using only water can cause rust and other deposits to form within the vehicle’s cooling system. Once these deposits have formed, they can be quite difficult to get rid of, and they can even inhibit the cooling system’s performance.

Engine coolant doesn’t require frequent replacement, which means that most drivers will never need to worry about the coolant in their vehicles. New vehicles come filled with coolant, and, in many cases, the coolant doesn’t require replacement for the first few years of the car’s lifecycle. Mechanics often check the coolant level and strength in a vehicle’s cooling system when the owner brings the vehicle in for a scheduled service, and as such, any problems with coolant are usually detected at this stage.

What exactly is engine coolant?

Engine coolant is an additive mixed with water and added to the cooling system of a vehicle. Most engine coolants are glycol-based and come in liquid form. Coolant is generally mixed with pure water in a 50/50 ratio before adding it to your vehicle's cooling system. Engine coolant is an important part of every vehicle, and using your vehicle without having engine coolant in the radiator can lead to damage.

Why is it recommended to use coolant?

Coolant is especially important for colder areas where the low winter temperatures can cause the water in a vehicle's radiator to freeze. When the water in your radiator freezes, the increased pressure caused by the expanding water can lead to cracks forming in the engine or other components. On the other hand, anti-freeze also increases the water's boiling point so that the water can effectively transfer heat from the engine to the surrounding air without boiling, giving you protection throughout the year. That is extremely important because when the water in a vehicle's radiator begins to boil, it longer effectively transfers heat.

It is important to note that engine coolant is highly toxic to humans and animals because glycol in the fluid gets converted into alcohol once it is ingested. The alcohol then becomes toxic and can cause serious problems for humans and animals if ingested. In addition, anti-freeze is reported to have a sweet taste, making it attractive to animals. It is always wise to handle any chemicals with care and ensure that children and animals cannot access dangerous chemicals like anti-freeze without adult supervision.

How long does engine coolant last?

Generally, engine coolant lasts for a very long time. In some cases, manufacturers recommend that engine coolant levels be checked every 15 years. Engine coolant is quite stable and doesn't deteriorate easily. Still, the additive becomes less active over time and might need replacement. Checking if your anti-freeze is due for replacement should be left to an experienced mechanic, as they have access to the required equipment and tools.

If it is determined that your vehicle is in need of a coolant change, the mechanic will proceed to drain and flush the cooling system before replacing the water and coolant mix with a fresh batch. Flushing the cooling system is important because it helps to remove any sediment or impurities that might have built up in the vehicle's cooling system over time. Impurities such as rust and other sediments can lead to degraded performance, and once these items have been removed, you might notice an improvement in the performance of your vehicle’s cooling system.

When is it recommended to change the coolant?

Since replacing the coolant in your vehicle’s cooling system is time-consuming, mechanics will usually check the coolant before replacing it. Because coolant can look perfectly normal even when it has degraded, specialised tests are performed to determine if the coolant is still working well before replacing the fluid is considered. This involves testing the acidity levels of the coolant/water mix to determine whether or not the anti-freeze is still providing the desired protection against corrosion. The mixture is also tested to ensure that it still provides protection against overheating and freezing.

It's unnecessary to replace the coolant if the tests show that the fluid is still working as it should. However, if any of the parameters are not met, it might be wise to replace the coolant so that your car remains protected against corrosion and extreme temperatures.

Although all vehicle manufacturers recommend that coolant should always be used, there are huge differences in the recommended coolant replacement schedules. Some manufacturers recommend that coolant should be replaced within the first 100,000 km and every 50,000 km thereafter, while others recommend that the fluid should be replaced every 12 to 15 years.

Do all vehicles require engine coolant?

Yes, in general, most vehicles require engine coolant. Although it is perfectly possible for vehicles to operate without coolant, it is not recommended. In fact, most car manufacturers recommend that coolant should always be used to ensure that your vehicle operates as it should.

Coolant serves many purposes, but one of the most important purposes is to protect the vehicle's cooling system against corrosion and other problems. Engine coolant is not something that needs to be replaced frequently, but it is well worth it to have the coolant in your car checked now and again. Replacing the coolant is a relatively inexpensive undertaking, and this is especially true when you consider the damage that can be caused when operating your vehicle without coolant.

The best time to check the coolant in your vehicle is just before the start of the winter season because the fluid is most important during the winter season when it prevents the water in your car’s radiator from freezing. However, if you notice any symptoms that might indicate that the fluid is no longer working optimally, have it checked immediately. Some of these problems can include overheating or poor cooling performance.

One of the easiest ways to notice this is by keeping an eye on the engine temperature. If you notice that your vehicle’s engine is running warmer than usual without any clear reason, the cooling system and coolant are likely due for a check. It is also important to stick to the recommendations provided by your vehicle manufacturer, and you can usually find information on when to check and replace the coolant in your vehicle’s instruction manual.

In some cases, it might be prudent to use a specialised engine coolant. Some of these cases include older vehicles that might require stronger anti-corrosion protection or cars that operate in particularly harsh conditions. For example, vehicles frequently used to tow trailers or carry heavy loads might require a stronger mix of coolant and water to ensure that the engine is kept cool. Also, vehicles stored outside in extremely cold temperatures might need additional anti-freeze protection to keep the water in the radiator from freezing. To this end, most coolant containers come with a chart detailing the exact mix of coolant/water required to protect the vehicle from freezing at a specific temperature.

Conclusion on using coolant

Engine coolant is often the last thing that we think about when getting into our cars, but this humble fluid plays an important role in ensuring that your car remains reliable and that we can travel from point A to B without any unwelcome interruptions. Although it might be tempting to avoid changing the coolant in your vehicle when you are pressed for time or working on a tight budget, it is well worth remembering that the cost to replace your engine coolant is minuscule compared to how much vehicle damage can cost you if coolant is not changed in time.


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