GOOD MOTORING
Keep the car COOL
H. Kishie Singh

Any day now summer will be here and temperatures will go up to 40°C. This is hard on your engine, which should run cool. The use of the air conditioner too puts extra stress on the engine and could heat it up.

After the winter, the first thing to do is to check out the AC. If it is not effective then may be it requires to be serviced and, if necessary, recharged.

When checking out the AC, keep an eye on the temperature gauge. This is an important gauge on your instrument panel. Any increase in temperature would mean that the coolant has lost its efficiency.

Coolant should be changed every 15,000 km. For most people this is about a year’s driving. So, you should change the coolant once a year and the time to do it is now, just before summer. You’ll be doing a great favour to the engine.

Coolant, like all consumables that you use in the car, has a life span. After a while it exhausts its properties. The coolant that I use has a range from -34°C to 130°C. This is in a 1:1 ratio. The lower end is really not that important but even if you dilute the coolant 1:2, the boiling point could be as high as 120°C. This is enough to ensure your car does not get heated.

You must also make sure that the radiator cap has a tight fit. Water in the radiator boils at 100°C. With a tightly fitted cap, like in a pressure cooker, the boiling point is raised. Add a good coolant and you will raise the boiling point to 120°C or 130°C.

For the average motorist, the lower or freezing point is not so important, unless you live high up in the Himalayas where you can experience sub-zero temperatures. In that case you will need a strong concentrate of coolant. A good coolant is an anti-freeze as well. You cannot afford to have water freeze in your engine. Since water expands when it freezes, the radiator can get easily damaged.

In some cases, the frozen water has cracked the cylinder block. This would have meant replacing the engine — an expensive exercise. A litre of coolant comes much cheaper.

Before you add fresh coolant, it should be a good idea to flush out the radiator. There are any number of brands selling a radiator wash. A good home recipe is caustic soda. It is easily available but use it with caution. It will cause irritation to the skin. Dissolve the caustic soda in a plastic mug of hot water. It will fizzle and splash. Exercise caution. Drain some water from the radiator and add the caustic soda solution. Refit the radiator cap. Now go for a drive. This means running the engine for 15-20 minutes. As the caustic soda circulates through the radiator and engine block, it will dissolve rust residue and any other dirt.

Back home, you should drain the water. Remove the radiator cap with care. The liquid is under pressure and will shoot out. The temperature could be well above 100° C.

Wash the radiator with cool water — your garden hose is ideal for this purpose. As the water drains out, keep filling the radiator with the engine running. Go on with it till clean water starts flowing from the radiator drain plug. Stop adding water but keep the engine idling till all the water has been drained. Switch off the engine and close the drain plug.

Now add the coolant/anti-freeze and top up with water. The engine should be idling. Please note, the water should be of high quality. I use distilled water which has no minerals or other impurities. The tap water you use may be dirty — even if you can’t see the dirt and impurities. This will surely clog up the radiator. Regardless of the coolant, this will cause the engine to heat up.

The radiator – or heat-exchanger as it should be called — is important for the well-being of your engine. Look after it.

Happy motoring.