By Matthew C. Keegan / Originally Published December 21, 2015 / National Automotive Parts Association /

As temperatures drop, a very important liquid is at work in your car to help keep it running. Known traditionally as “antifreeze” and sometimes thought of as “coolant,” this fluid runs in a circular pattern under the hood to maintain the temperature for key components, especially the engine. Without coolant, your car would stop running. Moreover, your engine might overheat and crack, so here’s how antifreeze protects your car:

Antifreeze Uses

Antifreeze is found in your car’s radiator and is typically refilled by pouring it into a separate reservoir connected to the radiator. This is necessary because directly pouring it into the radiator can be dangerous and might result in burns if the engine hasn’t cooled. The liquid travels in a circular pattern out from the radiator and is driven by the water pump.

Next, the fluid enters the engine where it removes combustion-generated heat, then it moves through the heater core, the unit that supplies heat to the vehicle’s cabin. Finally, the coolant returns to the radiator where the heat is jettisoned. The cycle repeats itself as long as the engine is running.

Beyond Water

Under typical ambient conditions, water mixed with corrosion inhibitors would be sufficient to cool the engine and supply heat to the cabin. But it’s in extreme weather conditions where another agent is required to get the work done. Water alone cannot stop a car from freezing or an engine from boiling over. Today’s formula for antifreeze will keep cars from overheating, and this is why it has become interchangeable with the term “coolant.”

When properly utilized, the solution lowers the freezing point of a water-based liquid. Likewise, it also raises the boiling-point elevation. Thus, your engine can operate just fine in temperatures well below the freezing mark. With antifreeze, it can also handle the high temperatures produced by the engine core as well as the high air temperatures that can compound the problem.

Coolant Degradation

Just as you need to change your motor oil, brake oil and transmission fluid because of degradation, coolant will also degrade. At some point the fluid may no longer get the job done, effectively putting your car at risk of breaking down. Antifreeze is composed of ethylene glycol, and that ingredient never wears out.

What the corrosion inhibitor ingredients that prevent the metal parts from rusting can wear out, and this effects the water pump and engine block. Fortunately, spent coolant is easily identified visually — a rusty or brown color indicates that the system must be flushed and the coolant replaced.

Replacing or Adding Antifreeze

Check your owner’s manual for guidance on how to change or fill the antifreeze. New antifreeze is typically sold as a 100 percent solution, but it should be mixed evenly with distilled water to create a 50-50 blend. Yes, you can also buy a pre-diluted solution featuring a 50-50 blend.

If temperatures in your area regularly drop to minus 34 degrees Fahrenheit, then a 60-40 or 70-30 antifreeze to distilled water ratio is necessary.

As far as coolant colors go, its coloration has no bearing on its effectiveness. Indeed, manufacturers use various dyes to achieve coolant color, although the pink and orange colors point to organic acids used instead of the silicates and phosphates found in the most common green coolant.

For more information on antifreeze uses and coolant, and how it benefits your car, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.

Photo Credit: cohdra_100_7996 by cohdra.

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