Have you ever put water into the coolant tank of your vehicle instead of using antifreeze? You wouldn’t be the first person to do so.
Many people believe it is okay to add distilled water instead of coolant, especially if you live in a hot climate. After all, why do you need a fluid to stop freezing if it never gets below 32-degrees Fahrenheit? So, is it safe to use water instead of coolant?
Sure, water is cheaper and might prevent overheating, but this isn’t all that coolant is good for. It’s needed for proper cooling system function. Let’s take a closer look.
What Exactly Is Coolant (Antifreeze)?
Coolant is a liquid blend made by mixing antifreeze with distilled water. Antifreeze is typically made of ethylene glycol or propylene glycol, and it helps keep the coolant in liquid form at both high and low temperatures.
Coolants are often color-coded (green, pink, blue, red, orange, or yellow), and each vehicle requires a specific type. Always check your owner’s manual or speak with your mechanic before topping up or replacing coolant.
How Does Engine Coolant Work?
As you drive your vehicle, the engine creates a lot of heat and needs to be continuously cooled to work right. If the engine weren’t cooled down, it would lead to complete motor failure.
The cooling system directs coolant flow into the passages of the engine block, as well as the cylinder heads. While the coolant passes through the engine, it absorbs the heat.
Heated fluid moves from the engine to the radiator. As it goes through the radiator’s thin tubes, it gets cooled off because of the air coming through the front of the vehicle. There’s also a fan blowing on the radiator to cool it off.
Cooled fluid moves back out of the radiator to the engine once again. This circulation of coolant is what runs the cooling system.
Importance of Coolant in Engines
Coolant is crucial for several reasons:
- Temperature Regulation: Coolant prevents engines from overheating during operation. Keeping the temperature stable enhances performance.
- Corrosion Prevention: Coolant contains additives that protect metal components in the engine and cooling system from rust and corrosion.
- Boiling and Freezing Point Adjustment: Coolant lowers the freezing point and raises the boiling point compared to water alone, reducing the risk of freezing in low temperatures or boiling in high temperatures.
- Fluid Movement: It aids in efficient fluid flow within the cooling system, ensuring that hot spots don’t develop in the engine.
Without proper coolant, the engine risks severe damage due to overheating or component degradation. Understanding the functions and importance of coolant guides you in making informed decisions about using water as a substitute.
Types of Engine Coolant
- Inorganic Additive Technology (IAT): This traditional coolant type often contains ethylene glycol and requires regular changes every two years or 30,000 miles.
- Organic Acid Technology (OAT): This modern formulation lasts much longer, typically up to five years or 150,000 miles.
- Hybrid Organic Acid Technology (HOAT): Combining elements from IAT and OAT, HOAT coolants offer benefits of both, often lasting up to five years or 100,000 miles.
What is the difference between water and coolant?
To better understand the difference between water and coolant, we’ll look at their boiling point, freezing point, and protection against corrosion.
Boiling point
Most motorists do not think about water boiling point before using it as a substitute for coolant. The truth is the normal operating temp of your engine is usually higher than the water boiling point. (212 degrees Fahrenheit).
But when you use 50/50 ethylene glycol, water-based antifreeze, and water, the boiling points increase to 223 degrees Fahrenheit.
However, the 223 degrees is closer to your engine’s normal operating temp. But a waterless coolant will increase the boiling point to 375 degrees Fahrenheit or more.
So, if you continue driving with water instead of coolant for an extended period, the engine will likely overheat.
The water will boil faster than coolant and evaporates, calling for the need to pull over for the engine to cool. Overheating engines can cause catastrophic engine damage, leaving expensive car repair bills on the table.
Freezing point
You may not bother about the boiling point if you live in a colder temperature. But the fluid may freeze if you live in a colder climate area.
If the radiator cracks due to freezing, you need to fix it immediately. What if it happens in the middle of nowhere? Do not even attempt to drive with a cracked radiator because the entire cooling system is useless at this moment.
Corrosion protection
One of the major disadvantages of using water as coolant is that the compounds in the water will leave a deposit in the system, reducing cooling efficiency. Undoubtedly, water can corrode metal, and most cooling system components are built with metal materials.
These pose a threat to the cooling system, and that is why coolant is formulated with some additives to curb deposits and rust in the cooling system.
You may wonder, can I use distilled water instead of coolant since it has no impurities? First, you have to consider the boiling and freezing point of water. As explained above, engines are usually hotter than the boiling point of water.
Moreover, water can freeze in colder climates. So, it is not recommended to run with only distilled water.
Can You Use Water as Coolant?
Water should only be used temporarily as a coolant because its boiling point of 212 degrees Fahrenheit is higher than the engine’s operating temperature of 220 deg F (15.5 deg C).
Boiling water won’t do any good for cooling the engine; rather, it will add even more heat and cause it to overheat.
Furthermore, the freezing point for water is 32 degrees Fahrenheit; if temperatures outside exceed this mark, the liquid may freeze and expand, damaging its cooling system in the process.
Coolant‘s main job is to remove heat from an engine by circulating through it and absorbing heat. After passing through the radiator, coolant is cooled by air moving over it before returning it back into circulation in the engine for further absorption of energy.
Furthermore, coolant contains rust inhibitors and other chemicals that protect against corrosion in case you run low on coolant – can water be used instead?
Conversely, coolant has superior heat and cold resistance. A 50/50 mixture of coolant has a freezing point of -35 degrees Fahrenheit while a 70/30 mixture can freeze to -84 degrees Fahrenheit.
Furthermore, its boiling point is approximately 375 degrees Fahrenheit – far higher than the operating temperature of an engine.
Bottom line: Only use water instead of coolant in an emergency situation that requires you to drive your vehicle directly to a repair shop. Do not switch over to water as your regular coolant.
The Benefits of Using Coolant
Enhanced Engine Protection
Coolant’s corrosion inhibitors and other additives protect the engine from damage caused by heat, pressure, and chemical reactions.
Improved Cooling Efficiency
Coolant’s higher heat capacity and ability to circulate effectively ensure optimal engine temperature regulation.
Extended Engine Lifespan
By preventing corrosion and overheating, coolant contributes to a longer and more reliable engine lifespan.
Peace of Mind
Knowing that your engine is protected by a properly functioning cooling system provides peace of mind and reduces the risk of unexpected breakdowns.
The Risks of Using Only Water Long-Term
Overheating
Without a coolant, the water in your radiator will evaporate faster, especially in hot weather or when using heavy engines. Coolant has a higher boiling point than water, meaning it can withstand high temperatures without turning into steam.
Water, on the other hand, boils quickly under heat, which can lead to frequent overheating issues and possible damage to the engine.
Freezing and Damage in Cold Weather
During cold weather, water in the radiator can freeze, causing severe problems. Frozen water expands, which can lead to cracked engine blocks, burst hoses, and damaged radiators.
Coolant contains antifreeze components that lower the freezing point, keeping your engine safe in colder temperatures.
Corrosion and Rust
Engine components are usually made of metal, and water alone lacks the anti-corrosion agents found in the coolant.
Over time, using water can lead to rust and corrosion inside the cooling system, which restricts flow, damages components, and can eventually cause leaks. Proper coolant helps protect metal parts from rust and extends the life of your engine.
Reduced Lubrication of Parts
The additives in coolant don’t just prevent rust; they also lubricate the moving parts in the cooling system, such as the water pump. Water alone can’t provide this lubrication, which can lead to premature wear and tear on these components.
Using Water Instead Of Coolant In An Emergency
Real-world breakdowns rarely happen in perfect spots. Maybe you are far from a parts store, the coolant warning light pops on, and the reservoir looks empty.
In that situation, using clean water can keep the engine alive long enough to reach a safe place, as long as you treat it as a short bridge, not a new normal.
First step always stays the same: let the engine cool completely before opening the radiator cap or reservoir. Hot coolant and steam can spray under pressure and cause burns.
Once the engine is cool, you can add water slowly until the level reaches the mark on the tank. If the system was very low, keep an eye under the car for fast drips that hint at a leak you must fix soon.
Emergency top-ups work best with distilled water, since it lacks minerals that leave hard residue. If that is not available, bottled drinking water is still kinder to the system than hard, dirty tap water from a random spigot.
After the drive, the temporary mix should be drained and replaced with the right coolant blend as soon as you can schedule the job.
Preventing Coolant Issues
The best way to avoid coolant-related problems is to take preventive measures:
Regularly Check Coolant Level
Inspect your coolant level regularly, ideally once a month. Top up the coolant as needed, using only the recommended type and concentration.
Flush and Replace Coolant Periodically
Follow the manufacturer’s recommended schedule for flushing and replacing your coolant. This helps remove accumulated contaminants and ensures optimal performance.
Use the Correct Type of Coolant
Always use the type of coolant specified by your vehicle manufacturer. Using the wrong type can lead to incompatibility issues and damage to your cooling system.
Inspect Hoses and Belts
Regularly inspect your coolant hoses and belts for signs of wear, cracks, or leaks. Replace any damaged components promptly to prevent leaks and ensure proper coolant circulation.
FAQs.
Q: Can I run straight water as coolant?
If you’re asking, can you use water as coolant in a diesel engine in winter or summer, the answer is yes.
Using straight water in your car is okay in an emergency. However, driving with straight water for an extended period will be detrimental to the cooling system components and the engine.
Q: What can I use as a temporary coolant?
One of the questions we get over the phone in our garage is, coolant is low; can I add water? If you run out of coolant, you can use water as a substitute until you get antifreeze or coolant.
However, distilled water is preferably okay than tap water. In any case, you can use distilled or tap water in an emergency.
Q: How long can I drive with water in my radiator?
While there is no recommended time you should drive with only water in your radiator, you can safely run with water for 60 to 300 miles without any damage. Of course, this depends on the type of water you use and your climate conditions.
Q: Can I mix the coolant with tap water?
Do not mix coolant with tap water. Instead, use distilled or de-ionized water. Here’s why I said so; tap water has some materials that can form deposits and eventually rust the cooling system components and the engine coolant compartment.
This can lead to engine overheating over time, causing severe engine breakdown if not fixed on time.
Q: Will a car overheat with distilled water?
Using the best quality water is safe to prevent your engine from overheating when you run out of coolant. Ideally, distilled water is the best quality water for this purpose.
But, since the normal engine operating temperature is higher than the boiling point of water, the engine can overheat if you continue driving with distilled water for an extended period.
Q: How do I make my own coolant?
Get a 50/50 antifreeze and distilled water. Afterward, get a funnel and a cup and mix equal measures of the distilled water and the antifreeze.
Then, open the radiator cap and pour the mixture until the radiator is filled. If your car has only a reservoir tank, fill the mixture until it reaches the max line.
Conclusion
Using water instead of coolant can be tempting in a pinch but remember it’s not a long-term solution.
While it can cool your engine temporarily it lacks the protective properties that coolant provides. If you find yourself in a situation where water is your only option use it wisely and for short distances.
Always prioritize getting the right coolant as soon as you can. This will help ensure your engine stays in top shape and avoids potential damage from rust or overheating.
Taking care of your vehicle’s cooling system is essential for its longevity and performance so make sure you’re prepared for any situation.