How to flush out a car radiator?
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Flush your radiator in four safe and simple steps
You don’t need to be a mechanic to understand how important maintaining your vehicle’s cooling system is. A vehicle radiator is a relatively straightforward part. Flushing out the cooling system is a simple enough process that we can explain in a few easy steps.
Read on as we provide clear instructions on just how easy – yet vital – learning to flush out a car radiator is.
Understanding the Role of a Car Radiator
The car radiator is an essential part of any vehicle’s fully functioning cooling system. It helps keep the engine cool by dissipating heat.
At the most basic level, a car radiator functions as a heater core exchanger. Coolant absorbs heat from the engine and travels from the engine to the radiator which radiates the heat into the atmosphere. The cooled coolant then travels back to the engine to absorb more heat and repeats the process again.
Over the years, corrosion inhibitors in the coolant can degrade, and allow debris to build up in your cooling system. The system becomes less efficient, and the debris can clog and promote corrosion in your engine. A quick coolant flush will take care of that.
Step 1: Having the right supplies
Make sure you have all the necessary supplies on hand, such as coolant/antifreeze, and a garden hose for easy rinsing. You will need:
- Coolant/Antifreeze
- A Garden Hose
- Flushing Treatment
- Distilled Water
- A Funnel
- A Drain Pan (or a flat, wide container that can slide underneath your car)
- A Wrench
- A screwdriver set
Natrad supplies a variety of vehicle coolants and cleaning treatments for Australian conditions. Contact us for more information.
[H3] How to choose the right flushing treatment for your car
Here are some things to consider when selecting a flushing treatment:
- Ensure the treatment product is designed to remove deposits and debris from the car’s cooling system.
- Carefully read the instructions on the treatment product to confirm that you are able to apply the product correctly.
- Fast-acting flushing treatments can be hazardous to use so ensure you have the appropriate type for your requirements. Slower-acting flushing treatments are less aggressive and can take up to a week to clean the cooling system.
By taking into account these points and doing adequate research, you will be able to pick a flush solution that best meets your car’s needs, allowing it to run efficiently and keep cool even in hot weather.
Worried about picking the wrong solution? Don’t stress. Contact our vehicle radiator specialists for a recommendation.
Step 2: Inspect for damage
For your safety, always ensure the engine is cold before commencing an inspection or performing work on the cooling system. Check your radiator for loose fittings, leaks or damage to the radiator hoses or heater hoses. If you notice any issues, we recommend stopping the process right here and bringing it to your nearest Natrad store.
If everything is in order, continue on.
Step 3: Drain the old coolant from the radiator
Place a drain pan underneath the radiator drain point to catch the old fluid. Turn the heater control in the cabin up to hot.
Underneath the radiator, you’ll find the radiator drain valve. Some vehicles come with a thick, short hose clamped to the drain valve to make it easier to empty.
Direct the drain hose from the radiator into an empty pan, bucket or container and remove the radiator pressure cap.
Once all is ready, open up the radiator drain valve to allow the old coolant to start flowing out. Close the drain valve when it’s empty.
Fill the cooling system with flushing treatment according to the product instructions, and close the cap. Run your engine for the appropriate time needed to allow the flush treatment to work. This will help dislodge and dissolve any gunk and debris in the cooling system.
When completed, get back under the car, open the drain valve, and empty the treatment solution into the drain pan or container.
Use a garden hose with a little bit of pressure to rinse away remaining treatment solution and debris you can still see inside your radiator or coolant tank. Flush this out thoroughly.
Coolant and treatment products are considered toxic waste and can be harmful to the environment, people and animals. Ensure that you safely dispose of the treatment solution and waste coolant according to your local government regulations.
Step 4: Refilling the coolant in your car’s cooling system
First, you’ll need to know how much coolant your vehicle’s system needs. You’ll find this information in the owner’s manual. With that in mind, use distilled water to dilute your coolant/antifreeze concentrate to the specified solution.
Turn on your car’s engine. Open the radiator cap, and slowly pour your coolant solution into the radiator or coolant reservoir. Once it is full, leave the engine running with the radiator cap off for a few minutes.
During that time, the coolant level might drop as it works through the system. Turn off your engine and top off the radiator with more radiator fluid solution.
You’re done! It’s a good idea to check the coolant level regularly over the next few days in case it requires further topping up.
Frequently Asked Questions
How often does a car radiator need to be flushed?
Car radiators should be flushed whenever a cooling system part is replaced or every few years as a preventative maintenance measure.
Can I flush my car radiator myself?
Yes, you can flush your car radiator yourself with the right tools and proficiency. Make sure you read the flushing treatment manufacturer’s instructions thoroughly and carefully and are familiar with your vehicle’s cooling system parts. It’s wise to consult a professional mechanic if you feel at all unsure how to do it yourself.
Do you flush a radiator with the engine running?
No. You should not flush a radiator with the engine running. Flush your radiator with the engine off and cold to avoid any potential damage to the engine, and any injury due to contact with hot engine parts or hot coolant.
You can keep your engine running as you refill the coolant to help it work through the engine.
What can I flush my radiator out with?
You can flush your radiator out with an at-home mixture of water and distilled white vinegar, or with commercial radiator cleaner. Make sure that the cleaner is compatible with the type of coolant in your car; otherwise, it may cause an unintended chemical reaction and damage the system.
Can you flush a radiator without removing it?
Yes, you can flush a radiator without removing it. If there is easy access to the radiator and drain valve, then it may not need to be removed.
Is it safe to drive if my car’s radiator isn’t working?
It is not safe to drive a car for very long if its radiator isn’t working or has no coolant in it. Without the radiator, the engine is liable to overheat from cold in under 10 minutes.
If your car’s radiator isn’t working efficiently (or at all), then the safest thing to do is to call your roadside assistance provider or a tow truck.
It might be possible to drive yourself to a mechanic, but only if they’re a few minutes away. While you’re driving, keep an eye on your dashboard engine temperature gauge. If the gauge crosses the halfway mark, pull over safely and turn off your engine. Let it cool down fully before resuming your drive.
In a pinch, you can fill your car’s radiator with water. This isn’t a permanent or efficient solution, but it’ll let your car run for a few minutes longer without overheating and can help you reach your nearest Natrad mechanic.
Let Natrad Flush your Car Radiator for you
We’re always happy to see someone practice their engine maintenance skills. But if you’re nervous about the process, don’t saddle yourself with unnecessary anxiety. Bring your vehicle in, and our specialists will give it a thorough cooling system flush for you.
Contact Natrad to book your radiator flush appointment.
