Theory of Operation Turbocharger Lubrication— Engine oil under pressure from the engine lubrication system is pumped through a passage in the center housing and directed to the bearings, thrust plate, and thrust sleeve. Oil is sealed from the compressor and turbine by a piston at both ends of the center housing. RG8099 –UN–18NOV97 The turbocharger contains two floating bearings. These bearings have clearance between the bearing OD and the housing bore as well as clearance between the bearing ID and the shaft OD. These clearances are lubricated by the oil supply pressure oil (A) and the bearing are protected by a cushion of oil.
Discharge oil drains by gravity from the center housing to the engine crankcase. Turbocharger Pressure and Discharge Oil A—Pressure Oil B—Discharge Oil 9010 05 14 JC89288,000019F –19–30JAN06–2/2 TM2361 (24JUN08) 9010-05-14 450DLC Excavator Operation and Tests 062608 PN=262