June 30, 2022

Auto Avenue

Auto Avenue

Coolant vs. Water in your car.

Q: Can water be used instead of coolant?

Yes, water may be added to cool your engine. However, it is often not recommended because pure water boils faster than a coolant does hence making your engine overheat. Your vehicle’s radiator cannot work if there is not enough coolant in the engine. However, if you are wondering, “can I use water instead of coolant in an emergency,” then the answer is a yes. It would help you out of a situation whereby accessing water would be easier than finding a coolant. Therefore, if it is a do or dies situation, do not hesitate to use water.

Q: Which is better coolant or water?

There is a significant difference between coolant vs. water. When you compare a coolant vs. water heat transfer, water does a great job at removing heat more efficiently, but it has a low boiling point. However, a coolant is better because it is a mixture of ethylene and water, which protects against corrosion and offers a higher boiling point. Water helps keep your engine cool, although it does not match the efficiency of a coolant. With time, water in the system evaporates completely leaving your engine to overheat. Coolant also helps in the protection of inner car parts.

Q: What happens if you put water in the coolant?

You should avoid mixing coolant with ordinary tap water. This water usually has minerals that form deposits in parts of the cooling system or the radiator. Distilled water can be added into the engine but only temporarily. Typically, using water as a coolant is not bad for only a short time or in case of an emergency. However, water lacks corrosion or antifreeze inhibiting properties of an ideal coolant mix. Therefore, water should never be left to stay in the engine for long, more so if you live in the colder areas. If water froze inside the cooling system, the engine would fail.

Q: How long does coolant last in a car?

Engine coolant is made up of a mixture of water and antifreeze. The two are mixed in a 50-50 solution. While the time a coolant should last vary, it is estimated to be about 40,000 to 50,000 miles. This is about 3-5 years after which it should be flushed and changed. However, if you find that you have to refill the coolant constantly, you might want to check for leakages in the system. Also, most service shops advise that you ought to change a coolant more often than it is recommended in a maintenance schedule.

Q: What is the ratio of coolant to water?

The recommended mixing ratio of water to antifreeze is usually either 60:40 or 50:50. This often corresponds to antifreeze protection at the temperature of about -25º C to -40º C. the maximum mixing ratio should be 40:60 while the minimum 70:30. If you increase the amount of antifreeze does not lower the freezing point further. The most beneficial ratio that is recommended is a 50:50 ratio mix.


In as much a lot of people opt to use water in their radiators rather than the coolant, it is not a good idea. If you do not have access to any coolant and using water is the only option, then do so by all means. However, ensure that you buy a coolant the next available moment.

It thus goes without saying that between coolant vs. water, the coolant I the better option. Keep in mind that without a coolant, all the heat dissipated, which is usually two-thirds of the energy produced, may quickly damage the engine.

related article: About car cooling systems, learn more.