Damage to the turbocharger

The most frequent damage to faulty turbochargers

After the beginnings of the Turbo era hot engine stops and the oil deficiency were considered the main reasons for failure of the end of a turbocharger lifecycle, is it now the over-speed and failures of the VTG unit.

Due chip tuning or leaks in charge of leading the turbocharger speed rises disproportionately strongly. After a more or less long-lasting whistle noise adopt the majority then turbocharger with a rattling noise due bearing damage, or even with a broken shaft.

Impact damage

Schlagschaden Verdichterrad
Schlagschaden Turbinenrad

Impact damage because of penetration of foreign elements into the turbine- or compressor housing can be clearly seen at the compressor- and turbine wheel. By installation of a new turbocharger the induction air channel and the exhaust-fume collector have to be inspected in regards of foreign elements. Attention! Turbocharger with above mentioned damages must not continue to work by any means.

Dirty Oil

Schmutzriefen auf den Lagerlaufflächen
Schmutzriefen an den Lagerflächen

Dirty oil leads to turbocharger damages in form of scoring on the bearing surfaces. Where does dirty oil come from?

  • Abrasion because of engine attrition
  • Inferior value oil
  • Low quality or clogged oil filter
  • Sometimes after motor reconditioning because of insufficiently cleaned oil channels in the engine

Disturbance of the oil supply

Starke Verschleißspuren am Lager
Bläuliche verfärbungen infolge Ölmangels

Repeated, a few seconds lasting oil deficiency leads zu heavy wear marks on the bearing surfaces of the turbocharger.

  • Installation of the turbocharger without prefilling of the lubrication system
  • Too little oil and filter change intervals
  • Oil thinning by fuel/glycol
  • Longer engine time out
  • Operation in excessive sloping position
  • Loss of lubricant properties due to over speed of the rotor shaft


Kohlenstoffablagerung auf Läuferwelle
Bläuliche verfärbungen infolge überhitzung

Failure because of excessive high exhaust-fume temperatures or because of frequent turn offs of the engine without sufficient cooling periods leads to carbon sedimentations on the turbocharger and in the oil pipes, The bearing on the side of the turbine and the piston ring seal are extremely affected. Possible causes for this can be:

  • Clogging/narrowing of the induction air filter
  • Heated turn off of the engine
  • Inferior value oil
  • Incorrect engine adjustment


Starke Verschleißspuren an der Anlaufscheibe
Starke Verschleißspuren am Axiallager

Failure because of high speed range of turbocharger on tuned vehicles or leaking pressure hoses between turbocharger and induction tube. Because of the excessive speed range an extremely high vacuum builds up in before the compressor wheel, which causes the spacer as well as the axial-thrust to wear out quickly.

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