Coolant being added to a radiator. (Photo: 123RF.com)
Why do I need coolant in my radiator? Isn’t water enough?
I have this impression that coolants are anti-freezes.
These prevent the water in the radiator from freezing, which is not applicable to the weather in Singapore.
The coolant used in a car’s cooling system can raise the boiling point of water as well as lower the freezing point.
Without coolant in the radiator, cars in Singapore will overheat.
In fact, a 50 percent mixture of coolant – usually ethylene glycol-based – with water will raise boiling point to 108 deg C and lower freezing point to as low as minus 39 deg C.
The latter is, of course, not relevant to Singapore’s climate.
But having an appropriate amount of coolant in the car’s cooling system is necessary for a couple of other reasons (besides raising the boiling point).
Radiator coolant contains a rust-inhibitor. This is crucial, since water can cause rust.
If you do not have enough coolant in the radiator, rust will form over time.
And you can see this when the radiator water turns rusty orange.
In addition, the coolant has the property to provide lubrication to the water pump shaft, hence reducing wear.
Having a coolant mixture instead of plain water in your car’s radiator is therefore important and necessary.
REPLACING COOLANT
In addition to having coolant in your car radiator, you also have to flush the system according to the car manufacturer’s recommendation.
Like all essential fluids, such as engine oil, coolant is also subject to wear and tear.
It will eventually lose its efficacy.
That means it can no longer raise the boiling point to as high a level. The coolant may also lose its ability to inhibit rust.
If this is allowed to happen, you will have to replace your radiator.
Or, worse, the engine might end up overheating.
When this happens, there is risk of severe damage.
