Things you need to Know about Automobile Radiators

Because engines produce heat, a cooling system that consists of a radiator is employed to keep their working temperature normal. Radiators are heat exchangers used for cooling internal combustion engines, usually in automobiles. Other engines like piston aircraft engines, railway locomotives, motorcycles, stationary generators as well as some other similar engines.

automotive radiator

Radiators are common types of heat exchangers designed to transfer heat from hot coolant to the atmosphere. This is achieved by a coolant fan that sucks the heat of the radiator through blown air into the atmosphere. Today we’ll be looking at the definition, functions, parts, diagram, types, and working principle of a radiator used in automotive engines.

Read: How to Flush a Radiator in a Car


Radiator Definition

Generally, a radiator is a heat exchanger that is used to transfer thermal energy from one medium to another for the essence of cooling and heating. Radiators are consisting of a large area of the cooling surface and use the stream of air to take away the surrounding heat. with easy access to the coolant heat, efficient cooling is achieved.

Modern cars use aluminum radiators, but they are usually made of copper and brass. This is because of their high heat conductivity. their various sections are joined by soldering.

It is the obvious radiator is important in automobile engines. One of its primary functions is to allow heat to be blown away from the coolant. It also functions as a reservoir for coolant before entering the engine. this is why the malfunctioning of the component will cause significant engine damage caused by overheating.

The radiator is also used to cool the engine transmission system coolant. Another great function of some type of radiator is that hot coolant is separated from cold ones. Cold coolant stays at the bottom portion of the radiator while the hot ones flow to the top. So, by it moving to the down portion the heat is already absorbed by the cooling fan’s air.

Read: Symptoms of a bad radiator fan

Parts of Radiators

Below are the major parts of radiators and their functions:


The core is the major part of a radiator that serves its main purpose. It is a metal block with small metal fins which through it the coolant heat is a vent to the air surrounding the radiator. Cores are used to classify radiators, for instance, one-core, two-core, or even three-core radiators.

Pressure Cap:

As the coolant in the radiator is always under pressure, which helps to keep the coolant much hotter without boiling. This allows the system to be much more efficient. The function of the pressure cap is to bleed off the hot coolant since it rises at some point. The hot coolant could cause damage to the coolant parts if the pressurized cap not functioning well.

Outlet and Inlet Tank:

The outlet and the inlet portion of the radiator are where the flows in and out of the radiator. It’s located in the radiator head which is made of metal or plastic. From the engine, hot coolant flows through the inlet portion to the radiator and from the outer portion to the engine. The hose is used to make the connections.


Some cars use the same cooler as the engine transmission cooler. In the transmission system, the fluid passes through a steel pipe to ensure coolant circulation. This coolant is also cooled within the radiator because heat is also generated through an automatic transmission. Although some engines are designed with separate radiators for the transmission.

Radiator Diagram:

radiator parts

radiator diagram

Types of Radiator

The various types of radiators are classified according to their core. Below are the types of radiators used in automotive engines:

Tubular Core Type:

In these types of radiator, the upper and lower tanks are connected by a series of tubes that passes the water within the radiator. There are fins located around the tube for efficient heat transfer. It absorbs the heat from the coolant through the fans into the atmosphere. Due to the fact water passes through all tubes in this radiator type, a defect in one tube will affect the cooling process.

Cellular Core Type:

In the cellular types of radiators, the coolant flows through the spaces between the tubes. The core is made of a large number of individual air cells surrounded by the coolant. Air passes through the tubes while the coolant flows in the spaces between them. The cellular core radiator is also known as a honeycomb radiator because of its appearance. Unlike the tubular type, clogging in the tube affects a small part of the total cooling surface.

Working Principle

With the above explanation, we’ve come to see the great purpose of a radiator in the automobile engine cooling system. Well, working is less complex and easy to understand. In a radiator, there is a tank on each side, and the inside contained a transmission cooler. There are inlet and outlet ports, which from the inlet port coolant flows to the tubes where they are exposed to cooling. The tubes are in a parallel arrangement, where they come in contact with cooling fins to draw away heat from the core.

As the hot water enters through the inlet port to the tubes, the cooling fan behind the radiator cools down the hot water in the tubes. The cool coolant then passes through the outlet port back to the engine to cool the hot part again.

Read: Understanding Radiator Pressure Cap

Watch the video to learn more about how radiator work:

In conclusion, we’ve covered the definition, functions, working, parts, and types of radiators. I hope you enjoyed the reading, if so, kindly comment, share, and recommend this site to other technical students. Thanks for reading; see you around!

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