How to Inspect and Replace Your Car's Coolant?

Coolant distributes heat from hot engines to assist avoid overheating and engine damage. It also serves as a lubricant for some engine parts and provides further antifreeze protection. If a car's cooling system solely relied on water, the engine would freeze in the winter and crack and fail.

You can easily check if you have adequate coolant, which is a blend of water and antifreeze, and if it is still protecting your engine from cold weather. You can check online by checking the freezing point to test your level of protection without having to wait.

Practical Coolant Terms and Information

The main ingredient in antifreeze is highly toxic ethylene or propylene glycol; coolant is created by combining antifreeze with water, which is something you should always do. Why is mixing water and antifreeze a must? Because pure antifreeze, in defiance of common sense, will freeze at a temperature greater than a 50/50 mixture of antifreeze and water. Moreover, water absorbs heat from your engine more efficiently than antifreeze.

The frequently recommended approach, which involves mixing 50/50 antifreeze and water, will freeze at approximately minus 35 degrees Fahrenheit, however, the exact details may differ slightly. Straight antifreeze, on the other hand, will freeze between 0 and minus 20 degrees. 

Even though 70% antifreeze offers the best freeze protection (down to minus 50 degrees), you shouldn't use stronger antifreeze than 50/50 if you can avoid it because of the previously mentioned heat transfer issue, which can cause your engine to overheat.

Selecting the Proper Antifreeze

Choose the appropriate colour of antifreeze for your car as they come in various shades. It used to usually be green, but these days orange is rather prevalent and comes in other colours as well. Your auto parts store ought to be able to assist you if your owner's manual is unable to clarify the situation. 

You might also verify the colour when you check the coolant level in your car; but, if it's old, it might have become cloudy, and it's possible that someone added the incorrect kind of coolant somewhere along the road.

It matters even what kind of water you use. Instead of using tap water in your radiator, it is advised to use distilled water because tap water includes minerals that might damage your car's cooling system. It is rare for systems to contain more than two gallons in total, so a gallon of distilled water (available practically anywhere that sells bottled water) should be plenty.

If your system needs coolant, which you shouldn't have to do unless there's a leak, it's normally easier to add a 50/50 "premix" that you can buy at the store. Otherwise, you risk using the incorrect amount of water to antifreeze since you won't know how much to add.

Examining the Level of Your Coolant

The overflow tank, which some older cars might not have, and the radiator itself are the two locations beneath your hood where you can check the level of coolant. If it's not immediately apparent, you may locate the overflow tank by following the small-diameter hose that connects to the filler neck of the radiator, directly below the filler cap. 

Regardless of engine temperature, the clear overflow tank can usually be visually inspected because it should have distinct levels labelled for "Cold" and "Hot." You might want to check the coolant level in the radiator in addition to the coolant tank, even if it is at the proper level and particularly if it is low. 

Because the cap you remove to inspect it retains a certain amount of pressure in the radiator—partly to help raise the boiling point of the coolant—the radiator needs to cool down for that, at least to the point where you can leave your hand on it. Should you abruptly release the pressure, the coolant may boil and shoot a geyser-like stream of extremely hot coolant. The radiator's coolant level should be checked and found to be exactly at the filler neck's bottom.

Checking the Freezing Point of Your Coolant

You will need to use some kind of tester to determine the freezing point of your coolant. Fortunately, basic ones aren't too expensive; they typically resemble a giant eyedropper with coloured balls inside. Other models may have a bigger tank with a pointer inside and a light lamp on top. 

Although the latter should be more precise, the former should work just fine. To test, remove some coolant by suction from the radiator or the overflow tank, and then review the findings. If it doesn't show a freezing point you feel comfortable adding plain antifreeze to the coolant to make it stronger. 

Most radiators include a drain plug at the bottom facing the engine side, in case you need to remove any coolant to make room for the straight antifreeze. Be aware that before testing again, the engine must run for a considerable amount of time to combine everything.

Additives for Coolant

Coolant replacement is advised by several automakers at specific periods, typically every two to five years. (Although some antifreeze, and some varieties thereof, might be "lifetime.") This is partially because antifreeze has long-wearing chemicals in it that help lubricate the water pump and lessen corrosion in the cooling system. Especially for more recent car makes and models, you should heed the automaker's advice because failing to do so could lose the engine warranty and damage your car's engine.