keeps them away from the moving parts, thereby cleaning the engine. For this, there are some cleaning agents added to the oil as well.
Why change engine oil?
With use, the oil loses its lubrication properties and picks up bits of metal particles, and this leads to a decline in its performance. This decline can be caused by a number of factors, and heat is a big one. The oil is made up of a number of different ingredients, each with a different molecular structure (especially mineral oils). The ‘lighter’ compounds among these evaporate quicker at high temperatures and leave behind the ‘denser’ ones. This leads to a change in the thickness of the oil and, consequently, its ability to move freely and lubricate the engine.
Another reason the engine oil deteriorates is the accumulation of contaminants. These include dirt from the air intake system and tiny metal particles from the wear and tear of engine parts. Then there are the by-products given off by the combustion of fuel. These are generally carbon based and lead to the formation of sludge. All these impurities get collected and impede the oil’s ability to flow smoothly and consequently, its ability to lubricate.
If the oil can’t perform like it is meant to, it can lead to engine damage. This is why engine oil should be changed regularly. Car manufacturers’ recommended oil change intervals are based on distance covered or your odometer reading, and it’s a safe bet to follow this. Still, you should also periodically check the engine oil quantity and quality yourself, using the dipstick, and change or top up if necessary. And remember, an early change is always better.
Types of oil
When it comes to the type of engine oil you put in your car, you have three options—mineral oil, synthetic oil and semi-synthetic or blended oil. Mineral oil is extracted from crude oil just like petrol and diesel, but while the fuels are extracted from the more volatile constituents, mineral engine oil is made up of more stable and heavier components; those that burn at much higher temperatures. Mineral oils are the cheaper option,