How To

How do I … Cool down my vehicle’s engine?


If your vehicle is prone to running hot, it might help you and your vehicle to cool down knowing that ordinary water has more than twice the ability to dissipate heat (known as thermal conductivity) as common glycol antifreeze and coolant. However, the type of water you use makes a difference.

Tap water, no matter where you live, has numerous minerals in it that will damage your engine if it is used frequently. The most common effects of long-term use of tap water are hard water buildups of calcium and magnesium.

Overtime, this buildup will damage the efficiency of your cooling system and defeat the cost benefits of using water instead of coolant. Just 1/16 of an inch of hard water buildup can drop the efficiency of your cooling system by 40 per cent. Distilled water might seem like an easy fix, and is recommended by some online sources, however it’s not the answer either.

Distilled water is stripped of its minerals, leaving it chemically unbalanced. When this water encounters metal, it will try to strip electrons from those parts and still damage your engine.

If you want to use water to cool your engine, “softened” water is the key. Like distilled water, this is water that is stripped of minerals. With softened water, the minerals are also replaced with a sodium ion that makes the water more stable. As a result, the water doesn’t try to take electrons from the metals it encounters.

Some sources indicate that a 1:1 mix of glycol has a boiling point of only 10-degrees Celsius higher than that of water (with a 15-pounds-per-square-inch pressure radiator cap). Water’s boiling point is 100 degrees, and its freezing point is zero degrees. Engines can typically exceed these temperatures so the mixture of chemicals such as glycol can serve as insurance against liquids freezing in your engine.

However, if you’re willing to experiment, some gearheads even recommend using pure distilled water only in the summer (with an anti-corrosion agent mixed in) and as little antifreeze in water as possible to get you by in winter (you should flush your entire system once a year). Mixing glycol antifreeze at a 1:2 ratio, instead of the common 1:1 ratio, with water still gives protection down to about minus-15 degrees. Be sure to check with your owner’s manual before proceeding or call the garage that services your ride to find out what they recommend before you start. – Wheelbase Media with files from Cadeem Lalor

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