Causes of turbochargers failures

Damage caused by foreign objects
Damages caused by foreign objects entering the turbocharger on the suction or the exhaust side are clearly visible on the wheels of the turbine and compressor. Before replacing a turbocharger, check the purity of the intake and exhaust systems.

Damage caused by dirty oil
Scratches on the bearings are caused by contaminated oil. To prevent such damage, you should use good quality oils and filters – replace filter on the occasion of repair the turbocharger. Oil and filters should be changed regularly as recommended by the manufacturer. This type of damage can be caused by:

– blocked, damaged or poor quality oil filter
– engine wear
– failure of the overflow valve of oil filter
– poor quality engine oil

Interruptions in the supply of oil and a shortage of oil pressure
Interruptions in the supply of oil in repeated short periods of time causes polishing and firing the bearing surfaces.

Reason may be:
- replacement of the turbocharger without flooding it with oil
- changing oil and oil filter
- inappropriate to start the engine after replacing or repairing turbochargers
- low oil pressure
– oil pollution (for example fuel)

The severe shortage of oil pressure over an extended period (more than 810 seconds) in addition to polishing and firing of the bearing surfaces causes the discoloration. Shortage of pressure is the most dangerous form of interruptions in the supply of oil. Reason may be:

– bent, broken or stuffy cable lubricant turbocharger
– inefficient oil pump
– low level of oil in the crankcase
– loss of lubrication due to the too-long running of the vehicle on a big slope land

Overheating
The accumulation of spent oil is caused by excessive temperature exhaust or engine shut-off too quickly after work. It is recommended that you leave the engine after working for 2, 3 minutes at idling speed (time required to cool the turbocharger). The transition high temperature from exhaust side of turbocharger to central corps causes burning of oil and corrosion of the bearings of a turbocharger. Major damages occur in the ring, the grooves of turbine shaft and the bearing of the turbine.

Reasons:
– blocked or worn air filter
– too quick turn off the engine after work
– poor quality engine oil
– too rarely oil changing in the engine
– blow air and flue gas
– inefficient injectors
– ill-fitted turbine housing
– faulty lubrication system and turbocharger
– faulty drainage system of the oil (crankcase ventilation defects in the engine)

Turbochargers operating principles

The principle of turbocharger is simple. It consists of two rotors placed on a common shaft. One of them is located in the exhaust system and is driven by exhaust gas extracting energy from the engine.

The second rotor is located in the inlet manifold. Thanks to a specially contoured shoulders, and under the influence of rotation of the shaft he pumped air into the engine at a pressure higher than atmospheric pressure. Then the engine is running efficiently.

It’s because of the produced power which depends on the dose of fuel that was burned at a given time. You must provide enough oxygen to burning to be effective.

14 kg of air is required to burn 1 kg of fuel. More pumped air can burn more fuel respectively with the same speed and the same engine. The mixture burns more, so fumes are less toxic.

Turbo diagnostic