Engine Coolant

When Automotive Engine Coolant Should Be Replaced?

Engine coolant goes by many names

including radiator fluid, radiator coolant, or antifreeze. No matter what you call it, engine coolant is one of the most vital car fluids for any vehicle. It is a combination of antifreeze and water (usually a 50/50 mix), and serves a number of purposes for a car.

First, it runs through a vehicle’s radiator to remove any excess heat and prevent the engine from overheating. Next, since it contains antifreeze chemicals, it prevents it from freezing up in cold temperatures. But also, engine coolant prevents corrosion and works as a lubricant to the water pump and other internal workings.

So as you can see, radiator fluid is very important for a car or truck to operate safely and effectively. Continue reading to learn when your vehicle’s engine coolant should be changed, as well as, factory car maintenance scheduling, and more!

In addition to the base fluid, there are a small amount of other ingredients including corrosion inhibitors, antifoams, dyes and other additives. While these other ingredients make up only a small fraction of the coolant, they are what differentiate one coolant from another.

Diesel Engine Coolant

In a heavy-duty diesel engine, only one-third of the total energy produced works to propel the vehicle forward. An additional one-third is removed as heat energy by the exhaust system. The remaining one-third of heat energy produced is taken away by the engine coolant.

This heat removed by the coolant provides a balance in the removal of engine heat that is critical in ensuring that the engine operates properly. Overheating could result in accelerated deterioration of the oil and the engine itself.

While water provides the best heat transfer, glycol is also used in engine coolants to provide freeze protection. The addition of glycol slightly reduces the heat transfer of the water, but in most climates and applications, freeze protection is critical.

Nearly all engines use coolants with similar base fluids: a 50/50 mix of ethylene glycol and water. In some circumstances, industrial engines may use other base fluids, such as additized water or a mixture of propylene glycol and water.

Radiator Fluid Flushes

Changing or replacing the radiator fluid in your vehicle is referred to as coolant flush. Regular coolant flushes are vital for your vehicle because it inhibits corrosion, prevents over-heating, and provides lubrication to the internal workings of your engine’s water pump, radiator, and heater core.

To properly identify when your coolant is dirty, you must first know what the color of the fluid is when brand new. The primary colors of engine coolant are yellow, orange, green, and black. Check the color of your radiator fluid once every week. When this color starts to change, you know it’s time to change your radiator fluid.

But the most noticeable sign that it is time to replace the coolant is when your engine starts to overheat. The temperature gauge on your car’s dashboard will tell you how hot the engine is getting, and if you start to see smoke, it’s gone too far!

never run without engine coolant

Never Run a Vehicle without Engine Coolant

Never operate a vehicle with an overheating engine. Not only is this extremely dangerous, it causes significant damage to the engine. This can result in a costly repair, engine replacement, or even a totaled vehicle. As soon as you are aware your engine is overheating, take it to an auto so immediately and have it serviced.

All fluids should be changed, flushed, and replaced regularly for all vehicles. The general factory car maintenance schedule is every 3,000 miles or 6 months, whichever comes first. This includes motor oil, transmission fluid, brake fluid, power steering fluid, battery fluid, windshield wiper fluid, and in some cases, even transfer case lubricants.

But engine coolant does not need to be replaced this often. Most manufacturers suggest flushing the coolant every 24,000 to 36,000 miles, or once every 2 to 3 years. But if you are driving in hot climates or long distances regularly, then once per year is a better schedule.

Consult a licensed automotive service and repair technician for information regarding your make and model vehicle’s factory maintenance schedule. An ASE-licensed mechanic will have up-to-date knowledge and information for all make and model cars and trucks.