What You Will Need to Add Antifreeze to Your Engine
To add antifreeze to the cooling system, you’ll need the following:
- The correct type of coolant for your year, make, model, and engine. You can find this information in your vehicle owner’s manual.
- Distilled water.
- A funnel.
- A heavy cloth or rag.
- Work gloves.
- Eye protection.
How to Add Antifreeze to Your Engine
Caution: Do not attempt to remove the radiator cap or coolant fluid reservoir cap while the engine is running or it’s hot. Steam or hot coolant can escape under pressure and cause serious burns to you or someone nearby. Wait until the engine has cooled down to remove the radiator cap, which usually takes around 30 minutes to an hour after turning off the engine.
1. Locate the fill cap
Under the hood, identify where you should add coolant. If your radiator has a cap directly on it, or it’s on a filler neck nearby, that’s the best choice. Also, note if there’s a reservoir mounted to the side. It might have a pressure cap on it, or it could be a simple flip cap too. If you don’t have a radiator cap but there’s a reservoir, that’s where you’ll add the fluid.
2. Remove the radiator or coolant reservoir cap
Extreme caution should be exercised in this step. Wear eye protection and gloves as well as a long-sleeved jacket to protect yourself in case hot coolant sprays out. With the engine cooled down, place your rag over the cap and slowly turn the coolant cap counterclockwise. You may hear pressure hiss or a slight suction noise. If you do, pause until it dissipates. If coolant begins to bubble out, quickly close the cap or step away. Take the cap completely off when the noises are gone.
3. Mix the coolant (if required)
You have two types of coolant you can use: pre-mixed or concentrated. With pre-mixed, the engine coolant is diluted 50-50 with water already. If you choose concentrated, you’ll need to do this mixture yourself with distilled water.
4. Identify the fill level and add coolant
If you’re filling the radiator, add coolant until it’s completely full, just below the rim of the filler neck. On the reservoir, identify the markings for FULL and LOW that are stamped in the plastic. There may also be indications for HOT and COLD. With a cold engine, add coolant to the FULL or COLD mark. To get rid of as much air as you can during the fill, squeeze the upper radiator hose to ‘burp’ the system. Repeat it a few times until there aren’t any air bubbles heard or felt in the hose.
5. Install the cap
Install the coolant cap on the reservoir or radiator, ensuring that it’s tightened completely by twisting clockwise.
6. Bleed the air from the cooling system (if required)
At this point, run the engine until it’s at operating temperature. The temperature should stay within the normal range. If, in the unusual circ*mstance that it spikes to the red zone on the gauge or you get an ‘ENGINE HOT’ message, there could be an airlock. Consult a service manual to determine the best way to get rid of an airlock for your vehicle.
Tips to Keep Your Antifreeze Full in the Engine
How can you ensure your engine’s antifreeze level stays in a good range? First and foremost, follow your car maintenance guide for cooling system services and inspections. You should check your coolant at least every oil change and top it off if necessary.
Also, if you notice a coolant leak, pay close attention to the fluid level until the leak is resolved.
For engine coolant and any other parts or fluids you need, shop at AutoZone. Find everything automotive you could need, sorted by year, make, model, and engine size, to keep your car working like it should.
Frequently Asked Questions
How often should I add antifreeze to my engine?
You should check the coolant level at least during every oil change and add coolant as required. If you have a cooling system issue, check the antifreeze once a week or more.
Can I mix different types of antifreeze?
Coolant types have different chemistries and can react, either shortening their lifespan or causing issues inside your engine when mixed. Only use types that are either vehicle specific or expressly say they can be used with your make.
What happens if I don’t have enough antifreeze in my engine?
Low antifreeze levels can cause overheating, reduce your cabin heating performance, and contribute to worsening emissions and fuel economy.
Can I use water instead of antifreeze?
Antifreeze is a better heat conductor than pure water, and it protects your engine from corrosion and freezing. It’s not recommended to use only water in your cooling system.
