The fan in the car engine continues running for a while after the engine has been turned off. You might have noticed this and wondered why; this is simply because the car has to cool off so it won’t have any problem.
This article will answer some questions you might have such as how long does it take for a car to cool down, How does the engine cooling system work, how long does it take for a car to cool down for an oil change, and how long does it take for a car to cool down for a mechanical procedure.
We also provide you with tips on how to get your car to cool down faster.
How Long Does It Take for a Car to Cool Down?
A car engine takes a minimum of about 30 minutes to cool down before you can safely handle it. The cooling down of a car can also take as long as 1-2 hours, depending on the ambient temperature and other factors.
If you intend on working on the engine, make sure there is no steam coming out of the hood before opening it up.
An engine that is overheated brings out steam from its radiator. This steam can burn the skin if you open the hood before the engine cools down. Therefore it is important to wait patiently until the engine is cool.
Check the temperature gauge to ensure the engine has cooled down and the hood is safe to open.
Keep reading this article to know some of the measures you can take to make the engine cool faster. But first, let us discuss how a car’s cooling system works.
How Does an Engine’s Cooling System Work?
The cooling system of a car engine features a cooling fan, radiator, and water jackets that circulate coolant around the engine block and head(s).
While the coolant goes about different parts of the engine through the water jackets, it absorbs the engine’s heat and is cooled when it gets to the radiator. This process continues as long as the engine is running.
An indicator of the health of an engine is the temperature of the coolant in the engine. Maintenance is needed in a gasoline engine as soon as it reaches its coolant temperature limit.
If the coolant temperature limit of a gasoline engine is exceeded and it overheats, repairs might be needed before it starts functioning properly again.
A malfunctioning cooling process might cause serious problems to the engine, and a temperature increase can damage important components of the engine, which can be expensive to replace.
These damages caused by overheating can lead to total engine failure. For this reason, you have to take the warning light on the dashboard seriously when it indicates any sign of overheating.
It is possible for an overheated engine could “seize up,” which means that the heat has become so much that some internal component of the engine has welded together, making it impossible for the engine to operate.
This kind of problem can be very expensive to repair, and it can even make a vehicle completely lose power.
Also Read: Radiator Repair Options And Which You Should Choose
How Long Does It Take for a Car to Cool Down? (More Details)
As highlighted earlier at the beginning of this article, it takes a minimum of 30 minutes for the car to cool down.
The difference in temperature between the engine and the surrounding environment highly affects the cooling rate of the engine. That is why the amount of heat loss is always little when the car temperature is close to that of the ambient temperature.
Practically, a car is assumed to have cooled down when you can handle it safely without getting burnt. Cooling down can also take as long as 1-2 hours, depending on the ambient temperature and other factors.
Factors That Determine How Long It Takes for a Car to Cool Down?
The faster your car’s cooling process, the lesser the damage it generates to the engine.
However, some factors influence the cooling down of the car’s engine. Some of which includes:
- The quality and amount of insulation in the engine bay;
- How hot the engine gets While the car is functioning
- The amount or volume of coolant that circulates in the engine
- The temperature of the environment where the engine overheated.
- The material in which the engine block and head are made ( that is, the engine block made of aluminum cools faster than steel).
What Could Cause a Car to Be Hot for a Long Time?
Below are some notable reasons why a car engine can take a longer time than usual to cool down:
1. The Temperature of the Environment Is Too Hot
If your car overheats in an environment with a hot temperature, it will affect the cooling rate of the engine. Therefore it is advisable to park your car in a shade other than under the sun’s heat to cool faster.
2. There Is Not Enough Engine Oil
Engine oil acts as a lubricant to engine parts, reducing friction and reducing the heat produced by meeting parts. If the engine has insufficient oil to work with, it will take a longer time to cool down.
3. The Fan Belt Is Broken
The function of the fan belt is to transfer the motion of the electric motor to the fan that helps in the cooling process of the engine. If the fan belt is faulty, there will be no power transfer from the motor to the fan, making the fan impossible to rotate to cool the engine.
4. The Cooling Fan Is Malfunctioning
The cooling fan helps speed up the cooling process of the engine. Therefore if the fan malfunctions or is faulty, it reduces the cooling process.
5. There Is Blockage in the Radiator
The radiator features tiny tubes that circulate coolant all over the radiator fins, which helps cool the engine.
If these tubes are blocked, there will be a hindrance in the circulation of coolant, thereby reducing the cooling rate.
6. The Water Pump Is Malfunctioning
The Water Pump is responsible for circulating the coolant in the water jacket that envelops the engine. If it malfunctions, it will slow down the engine’s cooling process.
Basically, a car’s cooling system is made up of four major parts, namely, the radiator, the water pump, the thermostat, and the heater core.
These parts are connected by hoses that circulate the coolant through the system, including the car engine.
If a problem occurs in these components, the cooling system will not work effectively. This might lead to the engine heating up consistently.
If you notice your car overheats consistently, this will mean that there is a problem with the cooling system. Your car needs a checkup from a professional immediately before the engine is damaged.
Also Read: Car Overheating When Idle? (Here Is What to Do)
How to Cool Down Your Engine Fast
As stated earlier, “the fastest the car cools down, the lesser the damages on the engine. This being noted, below are some of the ways to speed up the cooling process.
1. Perform Rapid Cooling to the Radiator, Not the Engine
A perfect way to do this is to spray or pour water on the radiator. Be cautious not to do this on the engine as it can cause a sudden crack on the engine block.
2. Rev the Engine Quickly
Another way to speed up the cooling process is by starting the engine and quickly revving it for one to two seconds. This action will help in circulating the coolant through the water pump.
However, make sure there is enough coolant in your engine before doing this trick.
3. Turn Off the Engine but Turn the Key in the ‘On’ Position
Keeping the key in the “on” position after the engine has been turned on makes the fan continue running, thereby speeding up the cooling process.
4. Fan the Car Interior
You can fan the car interior by opening the back and front window of the car. After that, open the door on the opposite side of the car and swing the door back and forth. Repeat this process at least three times.
5. Start the Engine and Turn Your Car’s Air Conditioning Setting to the Max
If your car has an option to select the ‘external’ air setting, then this trick is possible.
To know if your car has this option, check if the AC switch of your car has an arrow that is entering the car.
When this external air setting is selected, cooler air from outside will enter the car. You have to leave the car windows open, as this trick will take some minutes to take effect.
6. Open the Lower Air Vents
In the car, hot air rises, whereas cold air stays down. Therefore, allowing cool air to enter the car through the floor openings will force the hot air to rise and go out through the windows.
7. Open the Car Windows
Another easy way to speed up the engine’s cooling process is by driving the car with the windows open for some minutes. This action will enable hot air from the engine and inside the car to escape. Continue this until the air in the vent becomes cooler than the outside temperature.
8. Switch to Recirculated Air and Close the Windows
This is another effective way of speeding up the car’s cooling process, and this should be done only if the air from the air conditioner is already cool.
How Do Car Fans Work in Cooling Down Cars?
The cooling fan in the engine is one of the important components of the car cooling system. If the car is running at a low speed, the cooling fan in the engine carries the air through the radiator.
Airflow is important in a running vehicle because it takes away the heat absorbed by the coolant. The vehicles’ fans are only functional when needed as they are controlled by temperature.
There are two basic types of engine cooling fans they are:
1. Manual Cooling Fan
Manual Cooling Fan is a type of fan attached to the engine’s drive pulley. This fan engages when the engine reaches a high temperature while running, and it is controlled by a thermal fan clutch, a component that senses heat being emitted by the radiator.
By design, the thermal fan clutch freewheels when it is not engaged. It is made up of silicone grease, which expands when exposed to heat.
A typical unit has a seal and a set of shaft bearings to retain the lubricant. It is typically bolted or attached to the engine’s water pump.
2. Electric Cooling Fan
The second type of fan is the electric cooling fan. The primary function of this Cooling Fan is to improve the engine’s performance and reduce its emissions.
The Electric Cooling Fan can be installed in front-wheel-drive cars and rear-wheel-drive cars. The cooling fan is activated through a computer by a coolant sensor.
The coolant sensor helps to detect an increase in temperature in the car, which is more than normal. When this temperature rise is detected, the sensor signals to close the fan relay control, which is protected by a circuit fuse.
How to Prevent Your Car From Overheating
Prevention, they say, is better than cure. That being established, it is safer to prevent the engine from overheating other than remedying the situation when this happens.
Below are some tips that will help you prevent your car engine from overheating:
- Always pack your car under a shade to avoid exposure to direct sunlight.
- If it is not possible to pack your under a shade, try covering the windshield with a sunshade when parking under direct sunlight.
- If your car is parked in a secured/safe environment, leave the widows of your car slightly open.
- Thrive to always maintain and service your car’s cooling system.
- Make sure your conditioning system is always in good working condition.
- Use a damp cloth to clean the surface of your car when it is too hot.
Watch this video for more tips on how to stop your car from overheating
How Long Does It Take for a Car to Cool Down for an Oil Change
The cooling of the car engine for an oil change is an important task as an oil change cant be safely done when the engine is too hot.
An oil change also can’t be properly done when the engine is completely cold because the viscosity of oil changes with temperature. Therefore the higher the engine’s temperature, the easier the oil flows.
There are two ways to get the engine to an optimal temperature for an oil change:
- If the car has been driven to its running temperature, switch off the car and let it cool for about 30 minutes.
- If the engine is completely cool, start the car and let it run for some minutes.
The first case mentioned above makes the engine get cool enough for you to safely get to the oil filter and make the oil change without burning yourself. While the second case helps get the oil to a suitable temperature to enable it to flow easily.
The time highlighted above is just an estimate and can be influenced by the temperature of the environment. So do well to work within your conditions and be careful not to burn yourself.
Also Read: How Much Oil Does My Car Need?
How Long Does It Take for a Car to Cool Down for a Mechanical Procedure
The amount of time to wait for the engine to cool down before replacing or inspecting parts varies depending on the kind of replacement or repair you intend to do.
For most tasks, a minimum of one or two hours is advisable to let your car cool down, but if you intend to carry out a major diagnostic test or open the engine block, it is advisable to leave the car overnight to allow it cool.
Before embarking on a mechanical procedure, dont just check the temperature of the part you will be working on; also, check the surrounding components.
These different components are made of different materials; therefore, their cooling rate varies. This can be observed in the case of hoses that cool faster than the metal parts they are attached to.
Frequently Asked Questions
Should I Let My Car Cool Down After Driving?
If the engine has been under high load, there will be hot spots within the engine that you want to cool down before the coolant stops circulating. This will help avoid long-term damage, such as the warping of materials due to excess heat. Generally, know that is not necessary if you have been driving normally.
How Long Does It Take a Car to Cool Down to Add Coolant?
If you Just embark on a short drive, it won’t take that long for the car to cool down before adding coolant as the radiator would not be very hot. Therefore an average of 20 to 30 mins would be enough. Nevertheless, if you had just embarked on a very long drive, it would take more time for the engine to cool down. If that’s the case, a minimum of 1 hour is recommended.
How Long Does It Take for a Car to Overheat?
It will take about 15 minutes for the car to overheat if there is no fluid in the radiator. However, if the car is subjected to a load like going at high speed or uphill, it will take lesser time to overheat. This will also depend on factors such as the temperature of the environment, the oil used, the design of the engine, and the engine’s cooling system.
Can I Pour Water on My Engine to Cool It Down?
No, do not pour water on a hot engine or radiator. Doing this can cause a sudden temperature change and might result in the cracking of the engine block.
How Long Can a Car Overheat Before Damage?
About 30 to 60 seconds.
It takes as little as 30 to 60 seconds for an overheated car to start damaging various engine components like the valves or even pistons if the car is very hot.
Why Is My Car Still Overheating After Adding Coolant?
The cooling process of the car is facilitated by the air blown onto the radiator by the cooling fan and the air from the moving car. If this airflow is obstructed, the coolant will not be able to cool properly before being exposed to more heat. If the airflow is completely shut out, the coolant will boil, and this will make the engine overheat.
Should the Car Be Running When Adding Coolant?
No, this is not advisable.
Before adding coolant, make sure the engine is cool, the car is in neutral or park, the brake is engaged, and the brake is set.
In summary, A car engine takes a minimum of about 30 minutes to cool down before you can safely handle it. The cooling down of a car can also take as long as 1-2 hours, depending on the ambient temperature and other factors.
Do not try to lift the car’s hood if it is emitting steam. Observe the car’s temperature gauge as it shows when the engine has cooled down.