Difference Between Water And Coolant (All You Need To Know!)

Some car drivers would ask if they can use water and if they can use coolant, and what’s the difference between water and coolant. Many car drivers ask this question, and they would ask what the best to use is. 

So if you are also wondering what the difference between the two of them is, this article is best for you. In this article, we’ll be discussing the difference between water and coolant. Let us get started. 

Difference Between Water And Coolant

Are Water And Coolant The Same Thing?

No, water and coolant are not the same. There is a vast difference between water and coolant. Water will provide help in keeping your engine cool. 

However, water does not work the same as coolant. The water will boil much faster at a low temperature compared to the coolant. For some time, the water in the system will then evaporate fully. 

Is It Better To Use Coolant Or Water?

A lot of car drivers would choose to use water in their radiators rather than the coolant. This is not always a good idea. If you do not have any coolant with you, you can use water. 

However, you need to replace it with a coolant if you have the time. You can use water in terms of emergencies and if you do not have many choices at all. But this is not long-term. 

Make sure to change it with coolant if you get out of the situation. Coolant and water are not the same. The water might help cool down your engine, but it does not do all the coolant can do. 

The water will boil faster than the coolant in low temperatures. In winter, you can have an engine block crack if you drive your vehicle with just plain water. The engine coolant is produced so that it can keep your engine from being rusted. 

The water does not have this quality. If you do not have coolant, the heat made by constant internal combustion will damage your engine very quickly. Water is not enough to keep your system cool. 

If You Use Water Instead Of Coolant?

Sometimes, people have been using water alone to cool their engines. This is not the best choice. If you are in an emergency and have no coolant, you can use water instead of coolant because you have no other choice. 

It is understandable given the situation. Vehicles are made from metal. If your radiator overheats, there will be corrosion in your engine and your vehicle parts. 

When we say corrosion, the car metal will return to its original state. This means that they will degrade. If you will only use water in your radiator, your car engine will start collecting mineral particles. 

These specific particles will damage your engine. In hot weather, the water will boil fast. This means that your vehicle and the temperature of the surroundings of the vehicle will increase. 

The water will then boil inside your radiator if you will only use water. The process of evaporation will persist faster. Your vehicle can malfunction with that.

On the other hand, at cold temperatures, the water will then freeze. It will then cause severe damages to your radiator. You can even have a cracked head gasket. 

Can I Mix Water With Coolant?

Adding water into the coolant can cause contaminants in the radiator system. Your engine should be used with water rather than no coolant, but you should always replace it with coolant as soon as you can. 

If you add water to your radiator, you can dilute any coolant that can still be in the radiator. The coolant will have many essential functions, like preventing any corrosion in your engine. 

Can I Use Coolant Without Water?

There are many reasons why a pure coolant is not recommended to use in a car’s cooling system. One of the reasons is that pure ethylene glycol will freeze in between 0 degrees and minus 5 degrees Fahrenheit. If you mix the coolant with water, that is when the freezing point will then be lowered. 

If you need protection below the 0 mark, you must mix the coolant with water. Another reason is that pure coolants do not have the heat transfer abilities that a mixture of antifreeze coolant and water can do. The system will lose thirty-five percent of the heat transfer capabilities. 


In summary, people ask what the difference is between water and coolant. They ask this because a lot of people are using water only. 

However, some people are also using coolants. With that, there is confusion about water and coolant. Read this article for enlightenment.



Image credits – Canva

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My name is Hank, and I've been in the automotive industry for 27 years. I've been working in my own auto repair shop for the last 13 years, and now I want to help you here, on my blog. Let me know if you have any questions. Read more