The Ultimate Guide to Engine Coolants: What they are and why your car needs it

As the power source for vehicles, engines reach extraordinarily high temperatures. Without proper protection, an engine can deteriorate and even melt, requiring replacement at the cost of thousands of dollars. Many drivers know that their vehicle requires coolant, but others are unsure which type to use or what coolant is. When driving in harsh conditions, engine coolant, also known as antifreeze, is combined with water to prevent the radiator from overheating or freezing under extreme conditions. This article will cover our ultimate guide to engine coolants, what they are, and why your car needs them!

What is the role of engine coolant?

What exactly is coolant in a car? In order to keep your car working at its best, coolant conducts heat and provides antifreeze protection to the engine. Engine damage caused by freezing or boiling can be prevented by using coolant, which transfers heat. Protecting your coolant from freezing or evaporating is critical so that heat can be adequately transported. Average combustion temperatures are at 2,000°F, although they can rise to 4,500°F under certain conditions. Fuel is burned in internal combustion engines to generate electricity. The engine uses some of this energy to propel the car forwards. Heat is generated from the residual energy. 

Some of the engine’s heat is expelled through the exhaust valves. The remainder is contained within the engine block. It’s also possible for engine metal to melt if the coolant isn’t in direct contact with particular parts of the engine that need to be cooled. Engine cooling difficulties are to blame for a large percentage of all engine failures. In some modern cars, ventilation is restricted in the engine compartment, resulting in overheating in a matter of minutes without an adequate cooling system. Non-metallic elastomers (such as rubber and plastic) in the engine and cooling circuit are likewise protected by coolant.

How does engine coolant work?

The coolant reservoir on the radiator is where the coolant is stored before it’s pumped into the engine and its parts. In conjunction with a liquid cooling system, engine coolant is used. A liquid cooling system consists of many different parts.

  • The radiator helps to dissipate heat from the coolant by conducting it away.
  • Radiator hoses link together the cooling system’s many components.
  • When the car isn’t driving quickly enough to circulate the air, the fan kicks in to help.
  • The water pump, or coolant pump, is responsible for circulating coolant throughout the entire system.
  • The thermostat regulates the coolant’s temperature.

The coolant flows through the engine and back into the radiator when the engine is running. After cooling, the coolant drains out of the radiator’s bottom. An engine’s block and head are then cooled by a water pump, which subsequently pumps it back into the engine. When the coolant is returned to the radiator’s top, it is cooled once more.

What are the different types of coolant available?

Glycol-based coolants are used in all automobiles. Ethylene glycol and water make up the majority of standard coolants. Propylene glycol plus water make up another glycol-based coolant. Propylene glycol has a lower toxicity level than ethylene glycol.

Ethylene glycol, on the other hand, has a lower heat-carrying capacity than pure water, hence water would be the optimal coolant to employ if heat removal was the sole concern. Water, on the other hand, poses new problems. Rust develops on the iron engine components as a result. 

It then moves to other cooling zones. 

Even before the buildup blocks the radiator and clogs the cooling system, the corrosion it causes hinders heat transfer. Coolant acts as a lubricant to protect the engine from corrosion. Coolant also can thaw out when it freezes. Unlike water, it will not freeze and expand at shallow temperatures. Your engine will not break or experience more significant pressure due to this.

Vehicle cooling systems are serviced with three types of coolant on a regular basis:

  1. Inorganic Acid Technology Coolant 

The traditional coolant for older automobiles has been inorganic acid technology (IAT). Due to it degrading more quickly, this sort of coolant requires more frequent replacement. The colour of this coolant can be green or yellow.

  1. Organic Acid Technology Coolant

Organic acid technology (OAT) coolant is available in a variety of brands. They come in a variety of colours, including dark green, orange, and even pink and blue.

  1. Hybrid Organic Acid Technology Coolant

The HOAT coolant is a cross between an IAT and an OAT coolant. Most modern cars today use HOAT as a cooling fluid. Verify the type of coolant required for your vehicle by consulting the manufacturer’s specifications included in your owner’s handbook. If you buy the wrong product, you could have poor performance or even engine failure.

How often should I replace my engine coolant?

Coolant or antifreeze must be maintained and replaced in accordance with the manufacturer’s recommendations, just like all other engine fluids. Coolants designed for high-mileage autos, specific brands, or speciality additives may be necessary, depending on your vehicle. At least every 50,000 miles, the coolant system should be cleaned and replaced. Every 10,000 miles, specific newer models may need their coolant serviced. 

When the coolant is drained and replaced, corrosion and filth that could build up in the cooling system must be removed. Flush and refill the coolant if you see any foreign objects floating in it or if it seems rusty or colourless. It is realistic to assume that coolant education relating to product chemistry, use, and continuing maintenance is essential in generating a productive and lucrative environment regardless of the market in which the coolant is utilised. Preventive maintenance and using high-quality engine coolant from a reliable supplier can help keep an engine safe.


When purchasing engine coolants, consumers need to read the instructions that come with them. A minor divergence from the coolant’s instructions can cause it to fail to perform correctly. It would be best if you were meticulous, followed your car’s manufacturer’s directions to the letter, and completely comprehended what coolant is doing to your engine in order to keep it running at its best.


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