Coolant
Coolant is an oil-like substance used to transfer the heat away from the engine and to the radiator, which then transfers it into the air. Coolants work as a secondary heat sink for the engine, and help keep the engine from a temperature breakdown.
The primary purpose of coolant is transferring heat and preventing engine damage caused by freezing or boiling. Heat can only be effectively transferred with a liquid in the system, so it’s crucial to keep your coolant from freezing or evaporating.
How coolant works?
When coolant boils, the vapors formed do not transfer heat well, which means the engine metal can actually melt if the coolant isn’t kept in contact with certain places that need to stay cool. Some modern vehicles are made with tight engine compartments that don’t feature good air flow, which means they could overheat in a matter of minutes without a functional cooling system.
Coolant also serves the purpose of protecting metals and non-metallic elastomers (like rubber and plastic parts) in the engine and the cooling circuit.
Coolant typically consists of a 50-50 mix of antifreeze and water, though it can contain as much as much as 70% antifreeze for extreme cold temperatures. The 50-50 blend provides sufficient cooling for engines that operate at more than 200 degrees and prevents freezing in temperatures of 30 degrees below zero or lower.
Water alone has neither the cooling ability nor the protection against freezing that engines require because it boils at 212 degrees and freezes at 32, plus it can rust cooling system parts. Overheating can warp engine parts, and liquid expands when it freezes, so that can crack engine blocks and other parts.
Using straight antifreeze won’t provide more protection against freezing. The freezing point of antifreeze alone is zero, but a 50-50 mix with water lowers the freezing point to minus 35 and raises the boiling point to 223 or higher.
When the engine is off, coolant resides in the radiator. When the engine is running it gets pumped through passageways in the engine to absorb heat and then goes back through the radiator, where it is cooled by fresh air before circulating through the engine again. When a vehicle’s heater is being used, some coolant gets diverted to the heater core; the coolant warms the heater core, and the fan blows air warmed by the core into the interior.
What Sort of Issues Are Caused by Using the Wrong Coolant?
Without the proper coolant in your system, corrosion and component damage can lead to long-term effects. They’re sometimes latent, meaning it takes up to a year for corrosion damage, deposits, and plugging to cause a problem.
This is often misidentified by drivers as a radiator failure rather than simply acknowledging that the wrong coolant was used. If a radiator ends up badly corroded or full of plugging internal deposits, a malfunctioning coolant system is a likely cause.
“Oftentimes, people don’t think about the longer-term effects of corrosion and component damage,” says David Turcotte, Valvoline™ Technical Director. “Those can be latent: it can take six months to a year to get enough corrosion damage, deposits and plugging to create an issue from using the wrong coolant to have a visible problem. And by the time you get that problem, people have forgotten that they used the wrong coolant and think the radiator has simply failed as a part.”
And because coolant-related problems happen inside the motor, you might not realize the damage being caused unless you look at the cooling passages and the internal heat-transfer surfaces of the engine.
How Often Do I Need to Change the Coolant in My Vehicle?
The amount of time between coolant changes has been steadily increasing as engine technology improves.
As recently as two decades ago, changing your coolant every two years was the standard recommendation. Then, about a decade ago, that span increased to five years. In many of today’s modern vehicles, a cooling system is designed to allow up to 10 years (or up to 200,000 miles) before adding new coolant. In fact, some vehicles are filled for life.
AQAP Antifreeze was developed to last longer than universal coolants, which not only helps you protect crucial engine parts like gaskets and elastomers, it can lead to an improved lifespan for your vehicle and a reduced cost of ownership for you.
All vehicles aren’t made the same way—there are different materials of construction, different operating environments, different variable flow rates, different peak temperatures and pressures, different elastomers, different non-metallics and gaskets, you name it.
But one thing they all have in common is that they need to be protected. The OEM of your vehicle does extensive testing to determine what fluids, including coolants, should be used in the systems they’ve developed.
