You’re driving as soon as you an alert the temperature gauge begin to creep up. You traction over, safely inspect the coolant overflow reservoir and also find that it’s bone dry. You’re not delivering coolant, yet you do have water.

You are watching: Can you put water in the radiator

You might be asking yourself: “Can I put water in my auto radiator?”

Yes, friend can. And in the situation, girlfriend should. Water in your automobile radiator beats nothing, hands-down.

Water matches Coolant

A long time earlier — a really long time back — car ran v water in their radiators most of the time and people added antifreeze once it gained cold. Earlier then, cars were simpler, engines ran cooler and, uneven something was wrong, the boiling point of water (212 degrees Fahrenheit in ~ sea level) to be high sufficient that it operated just fine.

Modern engines run at higher temperatures. Running just water in her car’s radiator will guarantee overheating and damage, including to your cylinder heads and engine block. And most tap water has minerals that will certainly leave deposits inside the radiator, causing corrosion, shortening the life and further diminishing its capacity to cool.

Coolant provides a safety coating for her radiator to inhibit corrosion. A 50/50 mix of coolant and also water additionally lowers the freezing temperature and also raises the boiling suggest of the water in your car’s radiator. Instead of freezing and also cracking your engine block at 32 levels Fahrenheit, a half-water, half-coolant mix has a freezing allude of negative 34 degrees. The boiling allude takes a healthy jump from 212 degrees to 265, together well.

So, if you find yourself in the case we began with — asking yourself if you have the right to put water in my car radiator — make sure it’s for a quick distance only — simply far enough to purchase and include coolant. Then, view a mechanic to uncover out why girlfriend were short in the first place, repair any kind of leaks and flush the system, and add a fresh 50/50 mix of water and coolant v a funnel.

Why not Use simply Coolant?

That’s too lot of a an excellent thing. Remember, water has natural cooling properties. It’s why girlfriend drink it. The coolant’s job, past inhibiting corrosion, is extending those nature to do freezing or boiling happen exterior the normal variety of temperatures your engine experiences. Coolant by itself would freeze at 8 degrees Fahrenheit. Wouldn’t you quite be safeguarded to an unfavorable 34?

Check the end all the heating and also cooling products available on NAPA virtual or trust one of our 17,000 NAPA AutoCare places for routine maintenance and repairs. For an ext information on radiator failures, chat v a knowledgeable expert at your neighborhood NAPA AUTO components store.

Photo courtesy of Flickr.

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antifreeze, coolant, cooling system, engine antifreeze, freeze plug, radiator, radiator hose, water

Mike Hagerty view All

Mike Hagerty is one automotive journalist whose work has actually been featured on radio, TV, in print and online since 1997. He's the Publisher and also Editor the MikeHagertyCars.com, and contributes car reviews come the Los Altos city Crier and also losaltosonline.com. Ahead outlets have consisted of KFBK and KFBK.com in Sacramento, California, the ABC tv affiliates and also Hearst-Argyle and Emmis radio train station in Phoenix, Arizona; AAA magazines because that Arizona, Oklahoma, Northwest Ohio, south Dakota and the hill West and also BBCCars.com.