Flush and Fill: How To Keep Your Car Running Cool

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Surprisingly enough, a failed engine cooling system is the greatest cause of engine-related breakdowns. So in other words, if you get stuck at the side of the road, more than likely it’s because your car overheated. 

The best way to avoid this is to check your car’s coolant level on a regular basis and change it when your manufacturer recommends it. If you live in a harsher climate, such as sub-zero winters or blazing hot summers, it’s crucial your engine coolant is full and at the correct mixture. Extreme temperature swings also have a detrimental effect on rubber hoses and gaskets which can all contribute to an engine overheating. 

Just a quick note and to point out the obvious. A car’s cooling system gets very hot. Make sure the car has cooled before you check or drain the anti-freeze. Scalding hot antifreeze will cause burns and a potential trip to the hospital.
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Protect your eyes from potential dangers under the bonnet.
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Protect your eyes from potential dangers under the bonnet.

Draining the radiator

Before you begin, put on eye protection in case any of the old or new coolant is splashed in your face. If need be, jack the front of your car up and place it on jack stands to make it easier to get to drain plugs. Then place  chocks behind the rear tyres to keep the car from rolling off the stands.
Jack stands and tyre chocks will not only help you drain your radiator but keep you safe.
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Jack stands and tyre chocks will not only help you drain your radiator but keep you safe.
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Jack stands and tyre chocks will not only help you drain your radiator but keep you safe.
A typical radiator cap.
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A typical radiator cap.

Since you have waited for the engine to cool, we can start by carefully removing the radiator cap. It is possible there is residual pressure so taking it easy with the cap won’t cause any surprises.
Make sure your drain pan will hold all of the drained antifreeze.
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Make sure your drain pan will hold all of the drained antifreeze.

Locate your radiator’s drain plug and with a large drain pan under it, loosen the plug and drain the  radiator. Make sure you dispose of the old coolant properly and not in your regular bin.
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With the coolant drained, replace the drain plug and fill the radiator with water from your garden hose. It is also a good idea to add radiator flush with the water. This will help loosen deposits in the radiator and clean it out.
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Fill, drain and flush

Once the radiator is filled to the correct level with the tap water and flush mixture, start the engine. With the car’s heater running at high, let the engine run until it comes up to temperature. Since the heater core is part of the car’s cooling system, you want the water to circulate through it to ensure a thorough flush. 

Wait for the car to cool. Drain the radiator then fill it again with water from your garden hose. To properly flush the cooling system, you should do this process three or four times. The goal is to repeat the filling and draining process until the water you drain from the radiator is clear. Once you have achieved this, close all of the radiator’s drain plugs and get your new engine coolant ready.
Choose the right coolant for your car's engine.
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Choose the right coolant for your car's engine.

Check your owner’s manual for the correct  coolant mixture for your car. Manufacturers will recommend what coolant to use and how much water to mix with it. To make it easy, buy a pre-mixed coolant that meets your car’s requirements. If you do choose to mix your own, do not use tap water. Distilled water is the best choice as it does not have minerals in it which can contribute to corrosion. 

With the correct coolant, fill the cooling system and the overfill tank. Cap and tighten the radiator cap, then run the engine up to normal temperature. After running the engine, you may notice the coolant level is low. You should be able to add coolant to the overflow tank. If not, check the radiator after the engine has cooled. 

This do-it-yourself project is an excellent example of another way to get to know your car. If you have tackled oil changes, then maintaining your car’s cooling system is the next logical step. You get more familiar with the inner workings of your car and are comfortable knowing since you did the job, it was done right.
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WRITTEN BY:  ridestory
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