Replacing Your Engine Coolant
Written by Lee Wyatt (last updated April 4, 2012)
While many people may think that replacing your engine coolant is nothing more than pouring in a little bit more when you are low, that couldn't be further from the truth. This is one of those times when you will want to completely flush the system, and then replace the fluid so that you can prevent potential problems. Luckily, the process isn't all that difficult.
- Large bucket (preferably one designed for draining)
- Several clean rags
- Owner's manual
- 2 gallons premixed radiator fluid/coolant (50/50 mix)
- Get reacquainted with the manual. Before doing any kind of maintenance on your vehicle, including flushing and replacing your engine coolant, you need to take a look at your owner's manual. This will allow you to not only get an idea of where the various engine parts you need to locate are, but to get important information from the manufacturer. For example, if there is a specific type of coolant that they suggest you use.
- Locate the radiator. Once you are ready to begin draining the radiator, you need to locate the cap and remove it. When you open your engine compartment you can usually find the radiator cap by looking at the front (the part that is closest to you), usually somewhere in the middle. After finding the cap remove it and carefully set it aside so that you don't lose it.
- Find the drain. Look under the engine of your vehicle for the radiator drain. Usually this can be found on the left side (while looking at the front) of the car. On the average vehicle, this can easily be seen when you are under the vehicle facing towards the front. Typically this drain is closed off by a butterfly screw, but make sure that you have your drainage bucket in place prior to opening. Allow the radiator to completely drain before you proceed (this could take up to five minutes, so be patient).
- Reseal the drain. After draining your radiator, go ahead and reseal the drain. This can easily be done by replacing the drain plug, and turning it in the opposite direction used to loosen it. Once you have done that, place your funnel into the open radiator cap. Fill up a pitcher (preferably a large one) with water and then refill your radiator. With the radiator filled, remove the funnel and replace the cap.
- Run and drain. Turn your engine on, and allow it to reach the normal operating temperature before you shut it back off. Allow the engine to completely cool (it should only take 30 minutes) before you drain the radiator again. Simply remove the radiator cap, make sure that the drain bucket is in the proper location, and then remove the drain plug. Allow the radiator to completely drain again (which could take another five minutes). Once it has drained, set the bucket aside for later disposal.
- Reseal and refill. Reseal the radiator plug, replace the funnel in the open top, and then begin filling with the premixed engine coolant. Turn the engine on after you have poured in about one gallon of coolant, and let it run for about 15 minutes to remove all the air bubbles in the system. Begin pouring in the second gallon of premixed coolant until the radiator is full. It will be full when you can see the fluid near the upper neck of the radiator when you look into the open top. Seal the radiator cap.
- Clean up. After you have sealed the radiator cap, begin cleaning up. Wipe up any spilled radiator fluid with a clean rag. Dispose of the old radiator fluid according to the laws and regulations in your city, and you are finished with the job of replacing your engine coolant.