A car engine converts fuel to a mechanical engine. Every activity a car can perform depends on its engine directly or indirectly. A car’s engine works at all times and generates heat continuously. Unlike other parts which get some spare time to get cooled off, the engine keeps on running for hours without a pause or break.
And for that reason, it needs a support system that helps it to cool down. In this case, it’s called a coolant. A car coolant keeps the temperature in check and makes sure other components don’t get damaged by excessive heat. In this article, we will learn about coolants, how they work, and their importance. So, let’s begin.
What is engine coolant?
Coolant or antifreeze is a special solution that regulates the temperature of the car’s engine. It runs through small channels, ensuring optimal temperature and enhanced performance in any weather condition.
A coolant is used to lower the freezing point and raise the boiling point to prevent overheating during extreme performance and prevent freezing in cold weather. Often mixed with additives a coolant also works as a lubricating agent and inhibitor from rust and corrosion.
How does a coolant work?
A coolant helps to dissipate the heat generated from the engine to prevent heat damage and maintain optimal performance.
- The coolant working system has small channels through the car engine. The coolant is sent through these channels to the engine block and heads.
- The coolant flows through these channels, absorbing heat generated by the engine.
- The heated coolant is then sent to the radiator fins through a rubber tube for cooling.
- Cool airstream entering into the radiator fins through the car grill cools down the hot fluid.
- The cooled fluid is sent back to the engine through the channels to absorb more heat.
- The coolant recirculates back to the radiator fins, and thus, the process continues as the engine performs.
Why Coolant is Important?
Coolant plays several roles apart from keeping the engine working in its optimal temperature range. Here are the key importance of coolant explained:
Temperature Regulation: The continuous combustion inside the engine generates heat. Without coolant, this heat can damage the internal parts very quickly. Water alone cannot dissipate this amount of heat, which will ultimately reach boiling point and evaporate completely.
Similarly, in extreme cold weather, when the car sits idle for too long, the water used as coolant turns into ice. That’s why it is mixed with glycol, which has a lower freezing point. Coolant plays the most important role in regulating the temperature needed for optimal performance.
Protection Against Corrosion: Coolant is further mixed with additives. These work as a protection layer for metal parts like engine blocks, radiators, and water pumps and prevent corrosion and rust formation.
Lubrication: Coolant also acts as a lubricating agent. The cooling, when passing through the channels, acts as a lubricator for the water pump and other moving parts of the engine, reducing wear and extending their life span.
Different types of Coolant
There are different engine coolant types used in different cars. They have different chemical compositions and colors and are made to fit different car needs. Here are the types of coolants you will find in the market.
Antifreeze Coolant
Inorganic Additive Technology (IAT)
This technology uses acidic additives like silicate and phosphates in coolants. Inorganic coolants have a higher freezing point making them a great choice for extremely cold weather and also give better protection from rust and corrosion. All in all, the inorganic coolants are a highly reliable technology made for exceptional car performance. The only disadvantage of IATs is that they need replacement typically once every two years to maintain optimal conditions for the engine’s performance. The additives in IAT give it a green color, and it’s not available in any other colors.
Organic Acid Technology (OAT)
Organic acid technology uses propylene glycol as an antifreeze. They are the most popular choice due to their compatibility with newer cars and various types of materials. They are free of silicate and phosphate and work equally well at preventing rust and corrosion. OAT offers great longevity as well needs to be flushed once every five years. OAT coolants may come in different colors, like pink, orange, red, yellow, purple, and dark green.
Hybrid Organic Acid Technology (HOAT)
Hybrid organic acid technology, as the name suggests, is a combination of OAT and IAT. HOAT coolants mix acidic additives like silicate or phosphate with organic acids. Together, they work as excellent corrosion inhibitors for aluminum and cast iron engines and other metal parts of the cooling system. HOAT coolants have an extended lifespan of 5 years or longer. These coolants are usually gold or yellow and are compatible with both old and newer car engines with metal components.
Phosphate-free HOAT or Hybrid OAT
Phosphate-free HOAT, also popularly known as NAP-free HOAT, is a hybrid organic acid technology that does not contain nitrates, phosphates, or amines. The special coolant formula makes it an ideal fit for diesel cars. Some heavy-duty cars that use Phosphate-free HOAT coolants are Tesla, Volvo, Mini Cooper, BMW, and many others. They have an incredibly high service life of 10 years.
Phosphate HOAT
Phosphate HOAT or P-HOAT uses phosphate as additives for specific engine needs. These formulas with greater levels of phosphate have an extended service life of 5 years and above. P-HOAT coolants work great against rust and corrosion formation. Most of the P-HOATs are pink or blue and are mostly used in Asian vehicles. The brands that use PHOAT coolants are Hyundai, Toyota, Honda, KIA, Subaru, Nissan, and others.
Silicated HOAT (Si-HOAT)
Silicate HOAT technology uses silicate additives as corrosion inhibitors. These technologies of coolants is a relatively new technology made for newer car engines. Si-HOAT has an extended lifespan that can work for over 5 years for passenger cars and up to 3 years for heavy-duty vehicles. Mostly preferred by European brands, Si-HOATs are used by Mercedes, Audi, Porsche, and others.
Characteristics of a Good Coolant
A good coolant should incorporate some basic characteristics, which may include the following:
- A coolant should have excellent heat transfer capabilities.
- It should be able to absorb high temperatures without any significant increase in its temperature.
- It should be able to handle a wide range of liquid temperatures without boiling or freezing.
- Coolants are low in viscosity and density so they flow easily through the channels.
- Coolants should not react with internal components
- It should have anti-rust properties and a low-foam tendency.
Conclusion:
Cars have become an integral part of our lives. You need to check its health just like yours from time to time. It’s important to understand your car and how it functions.
Coolants not only protect the car’s engine but also make the ride safe for us. Understanding its functions and importance will help you keep your car in optimal condition, enhancing its lifespan.
