You cooling system must be in good condition to be able to enjoy your car to the fullest. And if your car is overheating, then you have ton of issues that needs to be solved immediately.
In my previous post, I discussed the top reasons of engine overheating. In this post, I will teach you how to super flush your cooling system and refill with a fresh new coolant. Lets find out how.
First, Drain Your Existing Coolant
The first thing to do when flushing your cooling system is to drain your existing coolant. How to drain your coolant? Find your radiator. It is found at the front of your car behind your grill. It is that rectangular flat block that has hoses and a cap at the top.
To drain your coolant via the radiator, just find the pet cock, the radiators drain plug. This pet cock is commonly a plastic component that is found at the bottom of the radiator.
Now some radiators don’t have pet cocks. If this is the type of radiator you have, you need to pull out the bottom hose of the radiator to be able to drain the coolant.
Now open the pet cock to drain the coolant that sits inside the radiator. Take note that you can’t drain all the coolant as most of the fluid are inside the engine block. You have to flush the entire cooling system first.
Once your first drain is done, return the pet cock and start pouring distilled water into the radiator.
Pour Distilled Water and Run the Engine
After you drained the existing coolant in your radiator. Have your distilled water ready. Only use distilled water as it is de-mineralized type of water. Tap water is packed with contaminants and particles that can harm your radiator and engine. It can form sediments or scales inside your radiator that will restrict the flow of coolant. So only use distilled water.
Open your radiator cap on top of the radiator, and pour as many water as you can. Once the radiator is filled to the top, you have to bleed the system more by letting the air out. How?
Try pinching the top radiator hose where your radiator cap is located. And start the engine and let it reach its operating temperature. You may drive your car if you want for at least 20 minutes but don’t forget to return the radiator cap.
Doing this will help the coolant to circulate to the entire cooling system. Once your engine reached its operating temperature, your thermostat will automatically open to let the hot coolant out while letting the cold coolant into the engine block. That is the process of your car’s cooling system.
Now you are about to do your first flush.
Once you are satisfied on your engine’s temperature and that the water is fully circulated, stop the engine and you may open the pet cock to drain the water you’ve just poured in. This is your first flush.
Take note that the water in the pet cock is most likely hot so wear heat resistant gloves when doing your first flush. Also, never open the radiator cap as there is high pressure on top and opening the cap will burst hot water into the air, which may cause severe burn to your hands or even your face.
Once you opened the pet cock below the radiator and the water is flowing out, you may now open the radiator cap as the pressure has now been neutralized. This will help let the water drain much faster.
If you are hesitant and afraid of getting burned, then you may wait for 30 minutes to an hour before you drain the water in the radiator. But doing this will only drain less water that is just coming from the radiator, not the coolant that is inside the engine block.
So it is much ideal if you drain the water when the engine is still hot. Why? Because the thermostat is still open, which will help you to drain more coolant than just draining the coolant that is only in the radiator.
To do a second and third flush, just repeat this process. Some folks flush their system up to five times to ensure that they have clean fresh coolant circulating the system.
Time to Fill Fresh Coolant
Now that you have done your last drain, it is time to pour your coolant into the system.
Now, there are engines that are quite picky when it comes to coolant. These engines require specific coolant brand and specifications so you have to check your owners manual and check what coolant is the right fluid for your engine. If you neglect on using the right coolant, you might end up damaging your engine or getting an overheating issues.
But most engines accept different brand of coolants. Some folks even only use water in their engines, which of course is not advisable. Water easily boils making them to evaporate faster than coolant. Plus, if you live in places that has winter season, water inside your cooling system will freeze. So only use coolant, or a mixture of water and coolant.
Assuming that you don’t want to worry about mixing water and would like to go straight ahead of using pure coolant, you may do so of course.
Premix long life coolant are designed to be used alone and shouldn’t be mixed with water or any fluid. They last longer and are more suitable for most car engines.
Some of the best coolant brands are found on Amazon.
Just pour your coolant straight to your radiator until full. Once full, start the engine and let the air out of the system. Keep the engine warm until it reached its operating temperature.
Now make sure that all air has been bled out as air will create a space inside your cooling system. If you see bubbles coming out, that is a good sign and you should also see that the coolant level is still not full. So keep pouring coolant until you reached the point that the coolant is not going down the radiator.
Now close the radiator cap and fill your coolant reservoir with fresh new coolant. Don’t overfill and make sure that your coolant is at the correct level.
Drive your car for half an hour and see if your temperature gauge is above the normal middle mark. If your gauge is normal after a long drive, then you have successfully flushed your cooling system!
Conclusion
Flushing your cooling system is one of the most critical maintenance car works that you can do on your own. You don’t need special skills or tools to do this job. Plus, doing this yourself gives you that peace of mind and complete satisfaction.
Otherwise, neglecting any cooling system maintenance will lead to engine failure, head gasket damage, engine overheating and of course, stalling. All these leads to inconvenience and you will begin to doubt your car’s running capability.
So go ahead and flush your cooling system and enjoy an overheat-free engine for years.
Below is my own DIY coolant flushing video. It is in Tagalog but it has English subtitle. Enjoy!
