Lubezine Magazine Vol. 4 Lubezine Magazine Vol. 4 | Page 11

Consumer choices lubricants survey – GFK P.18 See also AIR OUT Cut-away section of a turbocharger Bearing Turbine Wheel AIR IN EXHAUST OUT Compressor Wheel EXHAUST IN bearings will overheat and get damaged which will lead ultimately to its failure. There are two primary reasons for restricted drainage. A blocked drain tube, due to either damage or a buildup of sludged oil or high crankcase pressure which can be due to restricted crankcase breather or excessive engine blowby. The turbocharger should be periodically checked to ensure that the oil drain tube and engine breather tube are free from damage or restriction. Correction of these conditions leads to longer turbocharger life. Abnormally High Exhaust Temperatures Elevated exhaust temperatures cause coking of oil which can lead to bearing failure. Extreme over-temperature operation can cause wheel burst. There are two basic causes of abnormal temperatures. The first is restricted air flow and the second is overpowering the engine. In either case the engine has more fuel than available air for proper combustion, this over fueled condition leads to elevated exhaust temperatures. Causes of restricted air flow can include damaged inlet piping, clogged air filters, excessive exhaust restriction, or operation at extreme altitudes. Overpowering generally is due to improper fuel delivery or injection timing. If over temperature operation has been identified, an inspection of the air inlet and July-September 2012 | Lubezine Magazine exhaust systems should be performed. The fuel delivery and timing should also be checked. Oil Contaminat