How Does a Radiator Work to Cool Off an Engine?

How does a radiator work to cool off an engine?
Experienced mechanics share their insights in answering this question :
Whether you drive a Jeep or a Toyota Camry, every combustion engine powered vehicle has one thing in common – they all generate heat. Although engines are manufactured out of steel and high-grade aluminum, if they develop too much heat, they will cause damage to engine components and restrict the engine’s ability to work efficiently. This is where the radiator and the cooling system come into play: to keep the engine’s core at a predetermined temperature for optimal performance.

Inside each water-cooled engine are a series of jackets and passageways that are designed to flow throughout coolant and water throughout the engine. This coolant is designed to absorb heat as it circulates through the engine. Coolant is able to flow through a motor thanks to a water pump that sucks water from a metal container of coolant and water known as the radiator. After the coolant has completed the cycle, it returns to the radiator to ’cool’.

How does a radiator work?

The radiator is much more than just a coolant collection device. It is designed with multiple tubes where the coolant is kept and circulates in a serpentine motion. As the vehicle moves forward, air from the outside is forced into the radiator coils, which removes a tremendous amount of heat from the coolant and water that was previously heated by the engine. If the temperature gets too hot, a fan attached to the back of the radiator forces air from the back of the radiator to accomplish a similar task.

Coolant is released through the motor when it reaches a predetermined temperature. This temperature is measured by a metal thermostat that is inside the radiator. When the water/coolant temperature is above that preset temperature, the thermostat is open and allows the coolant to flow under pressure supplied by the water pump throughout the engine and back to the radiator. When the coolant temperature has lowered below that temperature, the thermostat shuts and restricts the flow of coolant through the motor. This allows the motor to generate heat and produce power.

The radiator is typically located at the front of any vehicle, because it needs air coming from the outside of the vehicle to enter the coils and cool the water/coolant. It works together with the water pump, thermostat, and a series of coolant hoses to ensure your engine does not overheat. If any of these components that support the radiator and comprise the entire coolant system, the vehicle may overheat, leading to expensive repairs in many cases.

The best way to avoid radiator problems is to make sure to stay on top of radiator maintenance, such as adding radiator fluid as needed and having your coolant flushed every year.

How to Identify and Fix Common car Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced mechanics :

Air passing through the radiator draws the heat away by means of convection. The cooling fan helps to move a higher volume of air through the radiator. The coolant temperature drops and the coolant cycles back to the engine through the lower hose.
The principle of a car radiator is relatively simple. When driving, the momentum of the air cools the individual tubules, resulting in the hot coolant giving off heat. As a result, temperatures equalize – the coolant becomes cooler, while the space around the radiator heats up.
The coolant flows through the thin tubes that make up the core of the radiator and is cooled by the air flow through the radiator. From there, it flows out of the radiator, through the lower radiator hose and back to the water pump. By this time, the coolant is cooled off and ready to collect more heat from the engine.
Radiators primarily heat your room using convection. This convection pulls cool air from the bottom of the room and as it passes over the flutes, the air heats up and rises. This circular motion helps block out cold air from your windows and ensures your room stays toasty and warm.
During the combustion process, some of the fuel energy is converted into heat. This heat is transferred to the coolant being circulated through the engine by the water pump. Hoses carry the hot coolant to the radiator, where the heat is transferred to air that is pulled past the engine by the cooling fan.
A typical automotive cooling system comprises (1) a series of channels cast into the engine block and cylinder head, surrounding the combustion chambers with circulating water or other coolant to carry away excessive heat, (2) a radiator, consisting of many small tubes equipped with a honeycomb of fins to radiate heat …
engine coolant as they are the same and can be referred to as radiator fluid. Radiator fluid should be replaced regularly based on the type used, the number of miles driven and the age of the fluid. You can check your vehicle manufacturer`s recommendations by looking at the owner`s manual.
On most modern cars, the cooling fan is controlled by the Engine Control Unit (ECU) which gets a signal from the coolant temperature sensor.
Heating a substance makes the molecules move faster. Cooling a substance makes the molecules move slower.
However, there are two main categories of radiators in the automotive industry: tubular-lamellar and tubular and tape.
Phases of Quenching

The three stages of quenching are: Vapor stage (stage A or vapor blanket stage). Boiling stage (stage B or nucleate boiling stage). Convection stage (stage C).

Evaporation is cooling process .
Temperature sensors work by providing readings via electrical signals. Sensors are composed of two metals that generate an electrical voltage or resistance when a temperature change occurs by measuring the voltage across the diode terminals. When the voltage increases, the temperature also increases.
Heat is simply thermal energy. Energy will always naturally move from high areas (hot) to low areas (cool). Cooling involves speeding up this process, actively moving thermal energy from a product into a cooling medium and then away into the broader environment.
The boiler heats water until it forms into steam. The steam then travels up through the vertical pipe to the radiator where the thermal energy is given off through the fins. As the heat is lost from the steam, it slowly begins to turn back into water.
Thermostatic Radiator Valves are a different type of user-adjustable radiator valve that monitors the temperature of the radiator and automatically adjusts the room temperature to maintain a regular level. Once the TRV is set to the desired level, the valve automatically controls the heat output from the radiator.
The boiler heats water until it forms into steam. The steam then travels up through the vertical pipe to the radiator where the thermal energy is given off through the fins. As the heat is lost from the steam, it slowly begins to turn back into water.
Block Your Radiator`s Heat

The hotter a steam radiator gets, the more warmth it radiates. So covering it up with a blanket or sheet is a simple solution for limiting the amount of heat the radiator puts out into the room. Radiators use natural air convection to heat a room.

The boiler heats water until it forms into steam. The steam then travels up through the vertical pipe to the radiator where the thermal energy is given off through the fins. As the heat is lost from the steam, it slowly begins to turn back into water.
Block Your Radiator`s Heat

The hotter a steam radiator gets, the more warmth it radiates. So covering it up with a blanket or sheet is a simple solution for limiting the amount of heat the radiator puts out into the room. Radiators use natural air convection to heat a room.

Thermostatic Radiator Valves are a different type of user-adjustable radiator valve that monitors the temperature of the radiator and automatically adjusts the room temperature to maintain a regular level. Once the TRV is set to the desired level, the valve automatically controls the heat output from the radiator.
Block Your Radiator`s Heat

The hotter a steam radiator gets, the more warmth it radiates. So covering it up with a blanket or sheet is a simple solution for limiting the amount of heat the radiator puts out into the room. Radiators use natural air convection to heat a room.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Honda Civic 2008. AC stopped working suddenly and engine check light came ON for a day.Next day AC worked and no engine light.
ANSWER : Hi there. In both cases, when an AC system is not working and a warning light is coming on the dashboard, typically a professional mechanic will complete the same initial inspection, which is to download the stored error codes that triggered the warning light initially. This tends to give them an idea as to what is causing the problems. This could be something as simple as an electrical relay that is faulty or loose or an indication of a computer related "glitch". Either way, the best way to move forward is to have a professional mobile mechanic complete a check engine light inspection.

An inconsistent starter motor that occasionally works perfectly now will not work. Then engine will not crank at all.
ANSWER : Hi there. It is possible for the starter to fail. But before replacing the starter, make sure that the battery cables are tight and clean. Then check the starter relay and make sure that the relay is clicking. If the relay is not clicking, then check for power to the relay. If there is power to the relay but there is no click, then the starter relay would need to be replaced. If there is no power to the relay, then either the wiring from the relay to the ignition switch has a break in it or the ignition switch is failing. If there is power to the relay and power to the starter motor, then the starter motor needs replaced. If you need further assistance with your no start issue, then seek out a professional, such as one from Your Mechanic, to help you.

Hey Allen. I just rebuilt (?) the engine on my 06 Acura TL. Now the engine line went on. They told me the engine? can blow up if I
ANSWER : Hi there. I think it may be a good idea to find a new mechanic. Fortunately, our mobile mechanics are able to complete most diagnostic inspections and complete a lot of repairs services at your location, and on your schedule. In what you are describing above, the current issue seems to be with your EVAP system, which is designed to relieve pressure in the fuel tank and also collect harmful vapors before they escape into the air. Now, in regards to the car "blowing up"; that’s a bit dramatic, but it is important to have your issues repaired if it’s related to the EVAP system. Here is what I would recommend. Set up an appointment to have one of our mobile mechanics come to your location to complete a check engine light inspection – (click here to set up an appointment). This will allow them to download the stored error codes that cause the light to illuminate and determine what parts need repair or replacement. Then, they’ll be better prepared to provide you with a repair estimate and complete the repairs in most cases for you.

What Is the Difference Between a Water-Cooled Engine and an Air-Cooled Engine?
ANSWER : There are a few main differences between a water-cooled and air-cooled engine.

Air-cooled engines utilize an engine cylinder design that incorporates cooling fins all the way around the cylinder and on top of the piston cylinder head. These fins draw heat away from the cylinder and radiate away the heat. As the vehicle is being driven, the air is directed over the fins to dissipate even more heat. Some vehicles may incorporate a belt driven or electric fan to blow across the fins to assist in keeping the engine cool. Some engines use the hot air off of the engine to heat the interior of the passenger compartment. Engines that are cooled by air have a harder time maintaining a constant operating engine temperature. This can affect engine operation during colder conditions or extreme heat conditions.

Instead of fins used to keep the engine cool, in water-cooled engines the engine block and heads are cast solid but with internals passages throughout the engine block around the cylinders and over the cylinder in the cylinder head. The engine will utilize a water pump that is connected to these passages on the engine. The water pump can be driven by belt, gear or electric motor. The system has a radiator that is used to radiate the heat away from the water (coolant) that flows through the motor. A thermostat is put into a passageway from the engine to the radiator. The water or coolant temperature is maintained by the thermostat. The thermostat controls flow of coolant into the radiator. As the water pump is turned, the coolant is pumped through the engine. The coolant absorbs and transfers the engine’s heat from the combustion process. As the coolant gets heated, the thermostat will allow the flow to be restricted to the radiator until the coolant temperature reaches a set temperature of around 190 degrees at which time it opens the flow to the radiator. The coolant then flows into the radiator and the coolant heat is transferred to the radiator fins to be dissipated out to the surrounding air like the fins on the air-cooled engine. The radiator has electric or mechanical fans to blow air across the cooling fins. The thermostat opens and closes as needed to maintain a constant engine internal coolant temperature; engine temperature is controlled better that air cooled engines. The coolant can also be routed into the passenger compartment to flow through a small radiator called a heater core to heat the interior of the vehicle.

Some engines may use a hybrid design that uses a water-cooling system mixed with some of the air-cooled engine traits to help keep the engine cool and to lighten the added weight of a full-size water cooling system. These systems may use smaller radiators or thin lightweight radiators and engine designs that have air cooled areas to dissipate heat.

The advantages of air-cooled engines are that they are lighter without the use of radiators, water pumps, thermostats, coolant, or hoses. The disadvantages are that they cannot warm up fast and cannot maintain a constant engine temperature. This will affect engine performance and emissions in climate changes like extreme cold or hot temperatures. A cold engine requires added fuel to run properly.

The advantages of water-cooled engines are that they can warm up quickly and maintain the engine temperature better than the air-cooled design. This helps maintain engine performance and emissions. The disadvantages of a water-cooled engine is the added weight of the engine design along with added weight of the cooling system components like the radiator, water pump, coolant, and hoses.

Hi, I got my corolla 2012 engine overheated due to bad radiator, I replaced the radiator but the engine pick is not the same.
ANSWER : Hi There,
Depending on how severe the engine overheating before was, this may have resulted in a blown head gasket or a head gasket that may have partially caused a cylinder leak. When this happens, this can cause the compression in any given cylinder to drop as a result of the cylinder head gasket being damaged. As the gasket leaks and cylinder pressure (or compression) drops, this will result in a loss of power. A blown head gasket may cause a number of different symptoms. A head gasket that fails between cylinders will generally cause a misfire and potentially compression leaks from one cylinder into another. Low compression will eventually result in a rough idling engine. When the head gasket fails between a cylinder and the coolant port, coolant may leak into the cylinder causing it to be burnt with the fuel charge in the combustion chamber. This often results in misfires on startup, especially after the engine is run, turned off and restarted. I would suggest having a professional from YourMechanic come to your location to diagnose and inspect your vehicle to determine what the proper diagnosis may be.

My radiator is spitting out coolant onto my engine and the check engine light is on but no overheating and its sometimes dont want to start should I get a new radiator
ANSWER : Hi there:

Before you decide to purchase a new radiator and have a new radiator installed on your 2005 Nissan Murano, I’d recommend having a professional mechanic complete a car is leaking coolant inspection first. This will allow them to determine why your radiator is spilling coolant, and also what’s causing your check engine light to occur. It could be a faulty coolant line or other cooling system component is damaged. It might even be caused by an air bubble.

How Does a Radiator Work to Cool Off an Engine?
ANSWER : Whether you drive a Jeep or a Toyota Camry, every combustion engine powered vehicle has one thing in common – they all generate heat. Although engines are manufactured out of steel and high-grade aluminum, if they develop too much heat, they will cause damage to engine components and restrict the engine’s ability to work efficiently. This is where the radiator and the cooling system come into play: to keep the engine’s core at a predetermined temperature for optimal performance.

Inside each water-cooled engine are a series of jackets and passageways that are designed to flow throughout coolant and water throughout the engine. This coolant is designed to absorb heat as it circulates through the engine. Coolant is able to flow through a motor thanks to a water pump that sucks water from a metal container of coolant and water known as the radiator. After the coolant has completed the cycle, it returns to the radiator to ’cool’.

How does a radiator work?

The radiator is much more than just a coolant collection device. It is designed with multiple tubes where the coolant is kept and circulates in a serpentine motion. As the vehicle moves forward, air from the outside is forced into the radiator coils, which removes a tremendous amount of heat from the coolant and water that was previously heated by the engine. If the temperature gets too hot, a fan attached to the back of the radiator forces air from the back of the radiator to accomplish a similar task.

Coolant is released through the motor when it reaches a predetermined temperature. This temperature is measured by a metal thermostat that is inside the radiator. When the water/coolant temperature is above that preset temperature, the thermostat is open and allows the coolant to flow under pressure supplied by the water pump throughout the engine and back to the radiator. When the coolant temperature has lowered below that temperature, the thermostat shuts and restricts the flow of coolant through the motor. This allows the motor to generate heat and produce power.

The radiator is typically located at the front of any vehicle, because it needs air coming from the outside of the vehicle to enter the coils and cool the water/coolant. It works together with the water pump, thermostat, and a series of coolant hoses to ensure your engine does not overheat. If any of these components that support the radiator and comprise the entire coolant system, the vehicle may overheat, leading to expensive repairs in many cases.

The best way to avoid radiator problems is to make sure to stay on top of radiator maintenance, such as adding radiator fluid as needed and having your coolant flushed every year.

Hey Chris what direction is the radiator cooling fan Supposed to blow? Towards the engine or towards the radiator ? It is a 201
ANSWER : The fan should blow air toward the engine (i.e., same direction as the air flow when the vehicle is in motion). If the fan is not OEM, the air volume may be off and the electrical characteristics could be different. The wisest course is to remove the fan and install a GM supplied part. Furthermore, if the fan is not firmly held in place with the correct fasteners, there is a possibility of it coming loose and damaging other parts or causing personal injury. The fan must be bolted to the vehicle. If you desire that this be rectified, please request radiator fan repair/replacement and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.