Can I Use Water Instead of Coolant in My Car?

Last Updated:
Can I Use Water Instead Of Coolant in My Car

When growing up, maybe you could see your father putting a jerrican of water in the car when traveling. If you were curious enough, perhaps he explained to you that the water acted as a coolant. It could be you grew with the misconception that you need to add water to the radiator when the engine gets hot. Now that you already own a car, it’s time to clarify things.

Note that the more you drive, the more the engine continues to produce heat. If there is no coolant, you will experience an abnormal temperature gauge, and the dashboard will start producing a warning light. The extreme heat will cause the head gasket to blow or even the cylinder head to wrap if you ignore it. In extreme cases, the engine will get severe damage. The cost of replacement will be unimaginable. To avoid all these problems, why don’t you get coolant?

The main question remains, Can I Use Water Instead Of Coolant in My Car? Yes, you can use it only in emergency cases. Imagine traveling, and you get the warning signs. You rush out and add water. After a short while, the water will boil and evaporate faster. That means you will have to keep on adding water. Unfortunately, water lacks essential elements that protect your car from corrosion. During winter, water will freeze faster; hence you risk a cracked engine block. So what causes low coolant?

Causes of Low Coolant

You are already wondering what would cause the engine to have a low coolant. Here are some reasons.

1. A Leak In The Reservoir

A damaged or leaking reservoir will cause the coolant to go low. Call the mechanic to inspect and repair or replace the reservoir.

2. Faulty Radiator Cap

The radiator cap protects the liquid from escaping when the engine is rotating. Once the cap gets damaged, the coolant will leak.

3. Damaged Radiator Horse

A damaged/ worn-out hose allows leakage, thus lower the coolant level. Fix or hire professionals to fix.

4. A Damaged Head Gasket

A right head gasket will ensure that no coolant will escape either through the cylinder or even the engine block. Once the head gasket gets damaged, leakage will occur.

Signs of Low Coolant

a. Coolant Dashboard Light

In case of a leakage, the coolant level will drop. That’s dangerous since the engine will overheat. In return, the coolant dashboard light will turn red. Once you notice it, get a safe place and pull over. Before refilling the coolant, check the leak and fix it. If it’s a significant leak, seek professional help.

b. Sweet Smell

The anti-freezers or coolant have a sweet odor, buts it’s highly toxic. When dealing with it, ensure no pets or kids are present since ingesting it can be harmful. So, if you feel the smell when driving, it means the coolant is leaking.

c. Internal Heating System Problems

If you start experiencing a constant flow of hot/cold air, then the heater could be faulty.

d. High-Temperature Gauge Moving To Red

If you are keen, you already know where the needle of your temperature gauges points. Once the needle starts moving towards red, the coolant level is low.

e. Poor Gas Mileage

If you realize that the number of times that you visit the gas pumps has increased, trace the problem. Among the causes could be the issue with the coolant. Note that the engine operates well at the right temperature. Fuel will burn efficiently; thus, the car will have normal fuel consumption. If the coolant isn’t working correctly, the fuel consumption will increase.

You are lucky if your car is a new model. Once the coolant levels lower, there will be an automatic engine cut-off. That means your car won’t start until you add coolant. You may feel like it’s inconveniencing, but it protects the engine from severe damage.

What’s a Coolant/Antifreeze?

The anti-freezer comprises either ethylene glycol (EG) or even propylene glycol (PG). They come in different colors, thus making it possible to choose the best for your car. It has a sweet smell, but it’s dangerous. If humans or pets ingest it, it could harm or even kill them. When disposing of the used coolant, dispose of it properly to protect the environment.

Why Is Coolant Important?

Note that you are not supposed to use pure coolant. You need to mix it with distilled water. So, can you use water as a coolant? Some people think that there is no problem using either distilled or regular water. They are wrong. The mineral particles in the regular water accumulate in the radiator, thus blocking your coolant flow. That’s why you need to mix your coolant with the distilled water in a ratio of 50:50.

Get a fluid that will remain a liquid in extreme temperatures. When you add water to the coolant, the boiling points will increase to 275 degrees F. During winter; the freezing point is at -30 degrees F. That means there will be an efficient flow of coolant in your engine no matter the season.

1. Temperature protection – Whether it’s winter or summer, the right antifreeze offers protection on your engine.

2. Prevent engine failure – If there is low or no coolant in your engine; it will affect the lubrication of metals. In turn, friction during combustion will result in severe engine damage.

3. Prevents rust and corrosion – The right coolants have addictive’s that protect your car from corrosion and rust. But if you use the wrong one or even the existing one gets old, it will cause rust and corrosion.

4. Protects engine components – As the engine continues to produce extreme heats, the plastic and rubber components can melt. Coolant regulates the heat, helping them to leave longer.

You are already wondering how the coolant works. Check more information below.

Working Principle of Coolant

There is a continuous circulation of coolant within your engine system. As you already know, the engine produces extreme heat when the car is in motion. The water pump pushes the coolant through the engine block and also cylinder heads. The coolant absorbs the excess heat from the engine.

Since the hot liquid can absorb more heat, it circulates to the radiator and gets cooled. The cool liquid circulates back to the engine block and the cylinder to absorb more heat, and the cycle continues.

How is the radiator able to cool the hot liquid? It cools the liquid courtesy of air that flows from the outside through the car’s grills and the thermostat. During winter, instead of the cold liquid going to the radiator, it will continue circulating in the engine block. The thermostat will open and allow it to the radiator once it heats up.

Note that coolants come in different types and colors. Knowing the right one for your car is vital. Here is a list of the coolants you need to know about.

Types of Coolant

a. Organic Anti Freezers

If you are looking for a coolant that will protect your car from rust and corrosion, go for organic anti-freezers. The technology that is used to make it is called Organic Acid Technology (OAT). It lacks phosphates and silicates and comes in different colors. If you are using this coolant, you should replace it once your car hits 150,000 miles.

b. Inorganic Anti Freezers

Is your car an old model and you are wondering about the type of coolant to use? It could be you bought a second-hand vehicle and don’t have the manual. If that’s the case, go for the Inorganic Anti freezer coolant. You can quickly identify it since it comes in yellow or green color. It’s made using Inorganic Acid Technology, also known as IAT. It contains phosphate, silicate, and ethylene glycol. Once your car hits 30,000 miles, replace it since it can cause corrosion.

c. Universal Anti Freezer Coolant

As different car models increases, many companies are coming up with many coolants. The compositions and colors of the coolants are confusing for many car owners. As a result, people who put the wrong coolant, the car corrode bringing an extra repair cost. You can avoid confusion by getting a universal anti freezer coolant. Unlike other coolants where you have to add water after buying, a universal anti-freezer coolant is ready to use. Its low silica content protects your delicate engine parts from corrosion.

Since you can use it in any car model, you don’t have to buy different coolants if you have other cars. Universals coolant would do. Before adding universal coolant, flush the system first. Once you add it, it can last up to 5 years before replacing it. If you travel a lot, then replace it once the car reaches 300,000 miles.

d. Hybrid Organic Acid Technology

It’s also known as HOAT. Once it exceeds five years in your car, it’s time to flush it, but if you travel more, flush it once your car hits 150,000 miles. Identifying it in the markets is easy since it contains orange or yellow color. 

Antifreeze vs. Water

Antifreeze protects your engine from cold temperatures, especially during winter. On the other hand, water may not remain in its liquid state when the temperature goes too low. Maybe you’re wondering can you replace anti freezers with water. After all, water is easily and readily available.

The comparison between anti freezer and water:

1. Liquid Color

One of the most obvious differences is the color. Water is colorless, while coolant comes in different colors. Note that some coolant comes in green color while others are orange. The color is not for decoration, but it has meaning. When you buy a coolant that contains orange color, it means that the technology that has been used to make it is Organic Acid Technology. But if the color is green, it means it has silicate and is made using Inorganic Acid Technology. So next time you are looking for the coolant, don’t just pick any color without knowing what it contains.

2. Boiling

Another vital aspect to consider when choosing a coolant is the freezing and boiling point. The extreme temperatures of the engine require a coolant with a higher boiling point. Note that the boiling point of water is lower, and at 212 degrees F, water will boil. As the engine continues to heat, water will evaporate faster, thus exposing your engine to extreme heat. With the anti-freezer coolant, it will not evaporate even at a temperature of 275 degrees F.

3. Freezing Point

During winter, you can risk the coolant freezing and turn it into ice. Water freezes at 32 degrees F. Remember, you require a coolant that will remain in a liquid state even when the temperature is low. Unlike water, the anti-freezer coolant is still liquid even at a temperature of minus 20 degrees F.

4. Anti-Corrosion Properties

In case of emergency, you may lack distilled water and decide to use tap or mineral water. Note that the mineral elements accumulate in your radiator and can hinder the flow of your coolant. The anti–freezer coolant, on the other hand, contains anti-corrosion properties that prevent electrolysis and also chemical reactions that cause corrosion in your engine. But again, you require using the right antifreeze coolant to avoid getting the wrong results.

Pros and Cons of Using Water Instead of Antifreeze

Maybe you’re wondering can you put water in your radiator. Imagine getting all the symptoms that your coolant level is low or it’s over. You check in your boot and realize that you forgot to carry the coolant. Would you rather drive without any coolant, yet you have distilled water? That would be a bad option. Remember, driving when the coolant level or low or even not there, you risk damaging your engine. So, in case of an emergency, use water but don’t drive the car for long.

Note that one of the reasons your coolant level is low or over is the leakage. Once you get home, take time, and inspect the cause of the leakage. You can fix it or even call the mechanic to do the job. Don’t make the mistake of adding any coolant before flushing the entire system.

What Are The Benefits of Adding Water?

In case of emergency, water is readily available. Remember driving without coolant is risky to the engine and its components. Unfortunately, the mineral components on the water can easily contaminate the radiator.

When the coolant gets lower, many people prefer adding water. Remember that coolant contains properties that protect your car from rust and corrosion. If you had already added 50% water, adding more water against the manufacturer’s recommendations will only dilute your coolant. That means the property will not be strong enough to protect the engine from corrosion and rust.

When to Change Coolant?

You don’t have to wait to get warning signs to change the coolant. Note that, if the coolant overstays, it loses its anti-corrosion power. Instead of waiting to get the signs, wait for the car to cool first before checking your coolant condition. If it’s slimy or slippery, replace it immediately.

Maybe you are not used to opening the car. Luckily, the owner’s manual contains vital information on when you should replace the coolant. Avoid exceeding the time given.

Effects of Mixing Coolants 

Once you buy a coolant, don’t ignore the instructions. Some coolants may be ready to use, meaning that you are not supposed to dilute them. On the other hand, some require you to dilute them with water using a given ratio. Even if you are economical, don’t add excess water. The coolant will become weaker, thus will leave your engine exposed. Mixing with less water than recommended isn’t good either. The solution may be too strong for your engine.

What if one coolant level reduces and a friend offers a different type of coolant to you. You should not get tempted to add it. Check the manual first if those two coolants can be mixed. Otherwise, you risk an engine misfire. So you better add water and get to your destination. Before adding any other type of coolant, you should flush the system first.


If you get warning signs and note that your car has no coolant, the best option would be to pull over and add some. In case you have no coolant left, add water only if you intend to drive a shorter distance. Remember, you can’t use water instead of coolant for long. Its boiling point and freezing point can mess up your engine. Again it may contaminate the engine and lacks anti-corrosion protective properties.

Once you get home, avoid adding the coolant before flushing the system. When adding the coolant, check if it’s ready to use or how you are supposed to mix it with water. Avoid adding excess or less water since it may get too strong or too weak. Avoid mixing two coolants unless instructed to do so. Avoid waiting until you get the warning signs. Keep on checking the condition of your coolant and change when needed. Since it’s poisonous, dispose of it properly since it’s harmful to both humans and pets. When purchasing a coolant, check the manual first on the type of coolant you should use. Be careful of the colors and know what each color means.

Leave a Comment