Coolant and Thermostats in Warm Climates.
Are They Necessary? The Myths Dispelled!!

by Mick Farmer
Training Director - On Course Uganda

Every week I see vehicles that have either one or both missing. The owner/driver of the vehicle looks at me like I was the idiot when I say that they are a necessity to the correct running of a vehicle. But it has been running like this now for ages, they say. It won’t be for much longer, I reply, and you’ll soon have a hefty repair bill to boot. This usually grabs their attention!!

Coolant or anti-freeze, as it is known in colder climes, is recommended by all vehicle manufacturers. Any one who has run a vehicle in a cold country knows the importance of anti-freeze but why then should we put it in our vehicle in a hot country? The answer is two fold.

Firstly, coolant has a corrosion inhibitor, which does what it says. It prevents the build up of corrosion in the cooling system. I’m sure everyone is aware that if you leave a sheet of steel open to the elements it quickly gets covered with rust. This is exactly what happens to the cooling system of your vehicle if run with water only. Eventually the corrosion will build up until it starts to effect the efficiency of the main parts. ie. the radiator (replacements cost a small fortune), the water pump, the thermostat and the hoses.

Secondly, coolant raises the boiling point of the cooling system. Therefore, if part of the system does fail and the engine does start to over heat less damage will occur, as fluid loss by vapour evaporation is kept to a minimum. On then to thermostats. It’s too often that I hear people and so called mechanics saying that thermostats aren’t necessary in a hot climate. A thermostat controls the internal temperature of the engine and keeps that temperature constant. Most engines are designed to run at a temperature of 80 degrees Celsius and above.

I would like any one to name me a country that has a temperature that high!! If you run without a thermostat then parts of the engine will run too cool and this can cause accelerated wear. Also the engine as a whole will be running at uneven temperatures and therefore is susceptible to failures. Especially if the engine is made from dissimilar metals i.e. steel engine block with an aluminium (aluminium to my American cousins) cylinder head. If your thermostat becomes faulty by all means take it out but make sure another, correct, one is put in its place.

So if you’re unsure get it checked and put right. In the long run it will be cheaper and more reliable!!

Safe and happy motoring.

About The Author Mick Farmer is the training Director for On Course Uganda Limited, the leading off-road driving school in East Africa. He has worked in East Africa and Southern Sudan for over 10 years. His experiences include running food relief convoys into Southern Sudan through the Congo and managing workshops in Sudan, Northern Uganda, and Kampala. To read more about On Course Driving Courses please visit: www.oncourse4wd.com