Coolant Flush: What Is It and Its Importance?

May 7, 2023

A vehicle’s engine generates lots of heat that need to be released. The cooling system regulates the engine’s temperature and keeps it within the safe operating range.

As a car owner, taking care of your vehicle’s cooling system is important to avoid costly repairs and keep it running. One of the essential maintenance procedures for the engine cooling system is a coolant flush.

In this article, we will discuss what a coolant flush is, its importance, and how to perform one. Keep reading to learn more!

What Is a Coolant Flush

What Is a Coolant Flush?

A coolant flush is also known as a radiator flush. This procedure helps prevent sediment and rust build-up within the car’s cooling system. During a coolant flush, the old coolant is drained from the cooling system and replaced with a fresh coolant. Coolant flush prevents engine repairs or replacements that usually cost thousands.

What Is a Coolant

What Is a Coolant?

Antifreeze is also known as coolant. It is a green or bright yellow liquid used in vehicles to prevent the radiator from overheating or freezing.

This liquid must be mixed with water to function properly and keep the engine running smoothly and safe from extreme temperatures. Therefore, your vehicle must always have enough antifreeze/coolant to avoid issues related to extreme temperatures.

These antifreeze and coolants are made with glycol, providing an ideal temperature range when combined with water. Glycol helps the engine maintain a temperature optimal for its performance, allowing it to operate more efficiently.

Ethylene glycol (EG) is the most popularly employed glycol in antifreeze/coolant solutions. However, other more ecologically responsible fluids, such as propylene glycol (PG), can also be utilized. EG is known for its low freezing and high boiling points, making it ideal for various automotive cooling applications.

Why Are Regular Coolant Flushes Important?

The importance of a coolant flush lies in the fact that, over time, coolant can become contaminated and reduce its effectiveness. Here are a few reasons why coolant flushes are important:

1. It Removes Harmful Substances

Coolant flushes are essential in preventing damage and long-term issues with your car’s cooling system. Over time, rust and scale deposits accumulate, causing severe overheating and other costly problems if not properly addressed. Regularly flushing the coolant eliminates these particles.

2. It Prevents the Engine from Overheating

Coolant is a vital component of any car engine, as it helps to prevent the engine from becoming too hot. As the coolant circulates through an engine, it absorbs heat and picks up small amounts of dirt, sludge, and rust.

As time passes, the effectiveness of your cooling system and engine will gradually diminish. So, regular coolant flushes are needed to keep them clean and in optimal condition. This includes deposits or debris being removed from the system that may affect their efficiency.

3. It Lubricates the Water Pump

Regularly flushing and replacing your coolant helps maintain your water pump system. This process prevents rust formation and lubricates the components.

4. It Welcomes System Inspection

A coolant flush service often includes inspecting the cooling system. This lets an experienced mechanic examine your cooling system and detect potential problems before they cause issues.

How to Perform a Coolant Flush 

Conducting a coolant flush is an effective way to maintain your engine’s temperature. Flushing out the old coolant and replenishing it with fresh liquid ensures your car’s engine stays at its optimum temperature.

This section provides instructions for performing a car coolant flush and safety precautions when handling antifreeze.

Step #1: Prepare Your Car for the Procedure

Prepare Your Car for the Procedure

Before you start the coolant flush process, you must park your car on a flat and even surface. Leave it for around half an hour so the engine and radiator can cool down completely.

You must have some items to flush out your vehicle’s cooling system. Make sure that all the following materials are gathered before beginning any steps of the coolant flush.

Gather all the necessary supplies to ensure a successful coolant change. Get new bottles of coolant and a container with an approximate capacity of four gallons for the used coolant. This will provide enough fluid and storage to complete the task properly.

Gather rags to wipe away any coolant that may come in contact with your hands or other objects. Keep children or animals away so they won’t get exposed to potentially hazardous liquids and fumes.

Coolant may appear in various colours, such as green, orange, yellow, or red but is toxic. Despite its harmless appearance, you must handle it with caution and proper safety equipment.

Step #2: Wear Rubber Gloves and Safety Glasses

Wear Rubber Gloves and Safety Glasses

Wearing rubber gloves keeps your hands clean while working with messy fluids and within the confines of your vehicle. For added protection, wear a pair of safety glasses as well. This will protect your eyes from splashes or sprays of fluid during the process.

Step #3 Drain the Old Coolant from Your Car

Drain the Old Coolant from Your Car

First is to lift the engine hood of your car and locate the radiator fill cap. This is generally placed on top of the radiator. Open up the radiator fill cap and, if present, the plastic reservoir containing additional coolant.

Next, you need to get underneath your vehicle to locate the drain for the radiator. This is usually found directly beneath where the radiator fill cap is situated. Look around, and you should spot it fairly easily.

If you have difficulty locating the drain, refer to the owner’s manual for your vehicle. It may be labelled as a “petcock” instead of a drain. If you still need help after looking through the manual, contact an automotive professional to locate and identify the drain.

Position the container to collect your old coolant underneath the drain. Then, gradually open the valve to pour out all the coolant from your radiator. Leave it open until no further liquid is released, and then shut the outlet off again.

Step #4: Pour Distilled Water and a Radiator Cleaner Into the Radiator

Pour Distilled Water and a Radiator Cleaner Into the Radiator

Insert the funnel into the radiator reservoir and carefully pour the cleaning fluid and water. Then, add a gallon (3.8 L) of distilled water.

Distilled water is purified and condensed through a distillation process. This means it contains no additional minerals or other impurities that could accumulate in your radiator over time. Therefore, distilled water instead of regular tap water can help extend your radiator’s life by preventing mineral buildup.

Ensure that the funnel you are using is specifically designed for automotive purposes. This shouldn’t be the one usually used in a kitchen. Choosing a funnel with an appropriate shape and size is important. This is because it can make all the difference when working on your vehicle.

Before cleaning your vehicle system with water, consult the owner’s manual to determine the quantity and type of cleaner you need. This helps ensures you use the appropriate product and cleaner when cleaning your car, protecting its surface from damage.

Step #5. Start Your Car’s Engine

Start Your Car’s Engine

After completely removing the old coolant, it’s essential to have a radiator flush product like Thoro-Flush installed in the radiator. This will ensure that residual debris or deposits left over from the previous coolant are thoroughly flushed out of the system. Also, this will ensure that your vehicle’s cooling system is free from any potential blockages or contaminants.

Next, start your car and let it idle for around 10 minutes until the temperature gauge reaches the “normal” range.

It is highly recommended not to run your car with Thoro-Flush in its cooling system for over 20 minutes. This could lead to significant issues and complications arising within your vehicle. After starting the engine, set the alarm or reminder to ensure you remember how long you have been running it.

Once the predetermined time has elapsed, switch off your automobile. Then, let it rest until the motor and radiator cooled completely.

It is essential to ensure they are not hot before touching them, as this could cause serious injury. Let the car sit for a while to guarantee that both components have completely cooled down before continuing the process.

Step #6. Switch Off The Engine and Allow a 15-Minute Cool Down

Switch Off The Engine and Allow a 15-Minute Cool Down

Before performing any maintenance on your vehicle, turn off the engine and let it cool down for at least 15 minutes. This is extremely important to ensure the machine has reached a safe temperature.

Additionally, you should know that the cleaner and water used were heated by running through your vehicle’s system. These could cause injury if you handle them without allowing them time to cool down.

Step #7. Flush The Radiator with Tap Water

Flush The Radiator with Tap Water

Tap water should be used to flush your radiator until the drainage runs clear properly. Then, run your car with the heat on for a few minutes.

After this process, drain the radiator and repeat the procedure. Fill it with a gallon (3.8 L) of tap water each time. Do it until no more debris or dirt appears in the drained water.

Once all contaminants have been removed, finish by flushing with distilled water to eliminate all impurities.

Step 8: Refill Your Radiator With a New Coolant

Refill Your Radiator With a New Coolant

The best way to top off your vehicle’s coolant is to use a pre-diluted coolant from a trusted auto parts retailer. This ensures you do not need to dilute it yourself, as all the work has already been done.

Remove the radiator cap and pour it directly into the radiator. However, if unavailable, prepare to mix the full-strength coolant with water to achieve an even 50/50 ratio.

After pouring your coolant into the radiator, do not open the radiator cap when starting your car. You should notice a bubbling effect in the cooling system before the level of coolant rises. Once this happens, put the lid back on and securely fasten it.

Step #9. Top Off the Radiator until It Is Full

Top Off the Radiator until It Is Full

Fill the radiator to the brim with an antifreeze solution. After turning off your engine, allow it to cool for at least 15 minutes before you remove the pressure cap.

Inspect the inside of your radiator and ensure that the antifreeze is level with the fill line. Add more of the antifreeze solution until you reach this mark, if necessary.

Any unused or remaining solution can be carefully emptied into the overflow receptacle. You can also store it for future use when you flush out your system again. This is a good way to ensure that no liquid goes to waste and use your resources wisely.


How Often Should I Change My Coolant?

It is important to consult your vehicle’s owner’s manual to ascertain the recommended frequency for coolant fluid changes. Many auto manufacturers advocate that drivers exchange coolant at 40,000 to 50,000 miles. This interval may vary depending on the make and model of your car. So, you must review your owner’s manual for the specific guidelines the manufacturer sets.

How Much Does a Coolant Flush Cost?

The cost of a coolant flush varies depending on your vehicle’s coolant capacity and the chemicals used in the system. On average, most people pay between $100 and $150 for this service.

Will a Car Run Better after a Coolant Flush?

Coolant flush can provide numerous benefits, including enhanced health and protection. After the service, you should experience a noticeable engine cooling and performance improvement. These positive effects will be felt almost immediately and can help keep your vehicle running efficiently for a more extended period.

Schedule a Coolant Flush Today  

If you think your vehicle is due for a coolant flush, schedule an appointment with a qualified mechanic. They can perform the service and inspect the cooling systems for potential issues.

Having regular coolant flush helps ensure your vehicle runs smoothly and efficiently. It will also help avoid expensive repairs and improve your vehicle’s performance.

At Mad Man Motors, we understand the importance of regular coolant flushes. We offer top-quality coolant flush services that will help keep your car running at its best. Contact us today to get it done and experience the difference!

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