The turbocharger is in fact an air compressor driven by exhaust gases. Exhaust gases leaving the engine through an exhaust manifold are directed to the compressor chamber where a rotor is placed. This rotor in turn drives through a shaft the compressor rotor which is located on the other side of the unit (which is often called the “cold” side) which compresses the air feeding the engine. Since the compressed air contains more oxygen per unit, this provides better conditions for the combustion process. The extra oxygen is combined with an extra amount of fuel, oxygen can be used to increase power of the engine or, as in the case of diesel engine, it enables more complete combustion by reducing considerably the quantity of contamination emitted by the engine and improving its efficiency.

By increasing air compression, that is the amount of gas available in the same volume, it also increases its temperature. Higher temperature causes lower density which means that a smaller amount of oxygen reaches the cylinders than in the case of lower air temperature. In order to ensure higher effectiveness of the combustion process, a cooler is used for charging air (intercooler).

Very often the cause of turbocharger damage lies not in the unit itself but is the effect of external factors. Therefore, it is so important to determine the essence of the breakdown before another turbocharger is fitted. It will prevent another turbine breakdown because of a defect in the external accessories of the turbocharger.

• Oil contamination:

This appears as a result of using low quality oils and filters, and is also the effect of too infrequent replacement of engine oil
This constitute enormous risk for the moving parts of the compressor, causing rubbing off of bearing surfaces.
High contamination causes the formation of grooves and decalibration of bearings which results in damage to the shaft and housing

• Limited or no lubrication:

This may be the effect of blockage in the lubrication system or by the oil losing its lubricating properties

The reason for limited lubrication is obstructed oil pipes e.g. as a result of blockage or restriction of flow by incorrectly fitted seals. Dilution of oil with fuel also causes quick wearing of the bearings and shaft by increasing their operating temperature.

• Operation in extreme conditions:

Caused by too high pressure and temperature

The lubricating properties of the oil deteriorate and it is scorched on the shaft, undergoing carbonization and thus damaging it irretrievably. In addition, elements of blades may tear off from the rotor when the mechanical strength of the material from which they are made is exceeded and they may become deformed, which leads to sudden defect in the turbocharger.

• Contamination in exhaust and intake systems:

This appears as a result of incorrect functioning of the intake system and during assembly

Salt or sand, as well as any dirt and contamination, by bouncing from the walls of the compressor may lead to extensive damage to the blades. Furthermore, contamination in the exhaust manifold such as, for example, particles of rust also creates enormous risk for turbine blades rotating at high speed.