To replace or not to replace?

There are endless disputes between drivers about whether it is necessary to periodically - read: once a year to change the engine oil in the car. While most drivers agree that this should be done after heavy use of the car and after a long run, they are not so unanimous about cars that are not regularly driven. Meanwhile, in the engine oil, no matter how the car is operated, adverse processes occur that can shorten the life of the engine. Below we list some of the most important of them, which will dispel any doubts about the advisability of regularly changing engine oil.

Oxygen, which is harmful

During the daily operation of the car, harmful processes of oxidation of engine oil occur. The main culprit is oxygen, the interaction with which turns part of the oil components into peroxides. These, in turn, decompose to form alcohols and acids and, consequently, tarry substances harmful to the engine. If we add to this the soot formed during the combustion of fuel, and worn particles of parts of the power unit, we get a mixture that has an extremely adverse effect on engine oil. The latter loses its proper viscosity and ability to receive heat. Lack of proper lubrication also leads to a weakening or even abrasion of the oil film from the cylinders, which in the worst case can even lead to engine seizure.

Sediment that pollutes

Oxygen is not the only "poisoner" in motor oil. Various types of pollutants coming to it from the air also have an adverse effect. In combination with the above resinous substances, they form sludge, the accumulation of which makes it difficult and sometimes impossible to operate the lubrication system, for example, due to clogged filters. As a result, they cease to perform their functions and the oil flows out through the opened safety valve. The quality of engine oil also deteriorates under the influence of fuel. When driving on a cold engine, the fuel does not evaporate quickly enough (especially in cars with a faulty ignition system) and dilutes the oil, flowing down the cylinder walls into the sump.

Refiners that wear out

Not all drivers are aware that there are practically no improvers in used and not changed engine oil for a long time, the task of which is to improve the protective parameters of the oil layer - the so-called film on lubricated surfaces. As a result, the latter wear out faster, which in turn can lead to engine failure. As with refineries, this also applies to another function that motor oil must perform. What is it about? For the neutralization of harmful acids, especially sulfur derivatives, in all fuels: petrol, diesel and LPG. Properly functioning engine oil, which has an alkaline reaction, neutralizes the harmful effects of acids in the engine. This is essential to prevent corrosion of powertrain components, especially bushings and pistons. Heavily used oil loses its properties, and the engine is no longer protected from aggressive substances.

Oil to be changed

The dangers of driving with used and unchanged engine oil mentioned above should give you food for thought. Therefore, periodic replacements established by automakers are not fiction or whims. The accumulation of harmful substances in engine oil, combined with the metal particles of engine wear parts, creates an extremely dangerous friction substance that penetrates into all nooks and crannies of the power unit. To make matters worse, the oil filters are also clogged, causing the oil to be delivered at too low a pressure. The latter, in turn, can lead to irreversible damage to the peripheral elements of the engine, such as hydraulic lifters, bushings, and in cars equipped with turbochargers, their bearings.

So, periodically change the oil in the engine, even with low mileage, or not? After reading this text, probably no one will have any doubts about indicating the correct answer.