The facts

We have seen the vast applications of aluminium in the production of cars; a notable example is in the 2013 Range Rover where its all-aluminium monocoque shed 39-percent of the SUV’s body weight in comparison with the outgoing steel Range Rover. The clear advantages of adopting lighter aluminium (in comparison with steel) in car production are improved handling, better fuel economy (It’s been said over time that ‘reducing a medium-sized car’s weight by 100 kg would result in a saving of 700 litres of fuel during the vehicle’s lifetime’) and more power (horse-power) as the use of aluminium improves the weight to power ratio of cars.
In this discussion we will narrow down the topic to aluminium engines which started gaining popularity in mass production of cars as far back as the early 90’s after the initial challenges in ‘metal working’ and the added cost of adopting these processes were tackled. These barriers where further broken when Mazda engineers developed a method of welding together aluminium and steel – obtaining over 20 patents in the framework of developing the new technology-as first utilized in industrial production of parts for the new model of their RX-8 sports car.

Most perceive aluminium engines as being generally touchy with heat, in comparison to steel, but to combat this in modern day car production, cylinder sleeves and bearing surfaces of aluminium engines are lined with either steel or harder metals for durability. It’s even been said that new aluminium engines can last as much as their steel counterparts-lasting way above 200,000 miles (322,000km) or more- and we have witnessed this in most car products from top players like Toyota, Honda and Kia.

   The reality
Aluminium engines –combined cylinder heads and main engine block-are generally less tolerable to overheating; as they warp at the slightest upset. In plain words, you hardly can get away with an overheated aluminium engine which doesn’t handle heat as good as steel engines do.

What this means is that in as much as lighter aluminium drive-train members improve fuel economy and engine power, they are quite sensitive to the slightest uncontrolled heating which takes us back to the need for proper cooling of car engines.

The Verdict

Generally speaking, older car engines are quite prone to overheating. Very minor issues like temperature gauges giving false readings can end the life of a less tolerable aluminium engine. What this means is that if you have an aluminium engine edging towards 62,000miles(100,000km) you have to pay attention to your car’s cooling system comprising of the water pump, radiator, radiator fans(with shrouds),proper fluids and not forgetting the primary engine cooling-oil cooling.

Ensure you maintain your car according to your specified manual and change engine oil and filters in due time. With all these in place and on check, you can enjoy all the benefits of your aluminium engine over a substantial life-span.
http://www.autobaseafrica.com/the-truth-behind-aluminum-car-engines/