813653T Mercruiser DRIVER, Bearing

TURBOCHARGER SECTION 1 Thrust ring.2 Thrust bearing.3 Compressor cover.4 Thrust ring.5 Spacer.6 Clamps.7 Shaft.8 Nozzle.9 Turbine back plate.10 Lock rings (three).11 Sleeve.12 Turbine housing.13 Shims.14 Nut.15 Compressor impeller.16 Turbine wheel.17 Ring seals (two).18 Ring seals (two).19 Spacer.20 Retaining ring.21 Seal.22 Insert.23 Oil deflector.24 Bearing housing.25 Vent tube.26 Oil drain hole.27 Bearings (two).28 Sleeve.29 Oil slinger.The turbocharger is designed to increase diesel engine power output. The turbocharger utilizes diesel exhaust gases to drive the compressor impeller (15) for supercharging the diesel engine.Turbine wheel (16) is located in the turbine housing and is permanently secured to one end of shaft (7). The impeller is secured to the other end of the shaft by nut (14) to form an integral rotating assembly. To assure reliability and freedom from vibration, all parts of the rotating assembly have been carefully, dynamically balanced. The compressor impeller can be replaced separately.Vent tube (25) vents the oil cavity to the crankcase. Venting this cavity promotes draining of oil from the bearing housing, and therefore away from the seals, thus reducing the work-load imposed on the seals.The rotating assembly is supported by two full-floating, pressure-lubricated bearings (27). Filtered engine oil is supplied through passages in the housing to lubricate the shaft bearings (27) and thrust bearing (2). This oil aids in removal of excessive heat. Oil returns from the turbocharger to the crankcase through an external tube at (26). Thrust loads are absorbed by stationary thrust bearing (2) and rotating thrust rings (1) and (4). Oil deflector (23) routes the oil, thrown from the shaft and thrust rings, back to drain opening (26).Ring seals (17) and (18) on either end of the shaft prevent oil from escaping the bearing housing.Beside housing the turbine wheel, the turbine housing acts as a chamber for exhaust gases from the diesel engine. Gases are directed through the turbine housing into contact with the turbine blades by the nozzle (8).Shims (13), located between impeller (15) and sleeve (11), adjust the impeller-to-cover clearance.Always handle the turbocharger carefully to avoid damage to any of its components.Altitude Operation
Maximum turbocharger speed is determined by the rack setting, the high idle speed setting and the altitude at which the engine is operated. The rack setting has been set to permit the engine to be operated at the altitude given on the warning plate on the instrument panel or valve cover. The high idle speed setting is not the same for all altitudes. If the high idle speed or the rack setting is greater than specified for the altitude at which the engine is operated, serious damage to engine or turbocharger parts can result.The maximum altitude at which the engine can be operated is specified on the altitude warning plate located on the valve cover or instrument panel. The governor housing and turbocharger are sealed to prevent serious engine damage due to operation of the engine with incorrect settings or turbocharger nozzle. Changes to the turbocharger, rack setting, or high idle speed should be made only by a Caterpillar dealer serviceman.The engine can be operated at a lower altitude than specified on the warning plate without danger of engine damage, but with slightly less than maximum performance. When operated at a higher altitude, the rack setting and high idle speed setting must be changed only by a Caterpillar dealer serviceman. After making any changes, stamp the new altitude limit on the altitude warning plate.Also, stamp the new high idle, full load speed, and rack setting on the governor warning plate (if so equipped). Reseal the governor housing for continued protection.Sealing Of The Turbocharger
The turbocharger is sealed at the factory. Factory installed seals are identified by the letters CTCO. Dealer's, sealing tool assembly, impresses the letters DLR on the seals.
TURBOCHARGER FACTORY SEAL
1-Seal.Checking Bearing Clearances
A quick check of bearing condition can be made without completely disassembling the turbocharger. This can be done by inspecting the compressor impeller, turbine wheel, turbine housing and compressor cover. If there is no indication of either the impeller rubbing the compressor cover at A or the turbine wheel rubbing the turbine housing at B, the bearing clearances are generally satisfactory.A more reliable check of bearing condition can be made only when the turbocharger is disassembled and the bearings, shaft journal and housing bore diameter can actually be measured. See the SPECIFICATIONS for these diameters.
CHECKING FOR BEARING WEAR
A and B-Locations to check for scuffing.While the turbocharger is disassembled, carefully check the back surface of the compressor impeller for signs of contact with the cover. Contact in this area indicates a worn thrust bearing or thrust rings.Checking Turbocharger Shaft End Clearance
See the SPECIFICATIONS for normal and permissible shaft end clearance (axial movement). End clearance is checked with a dial indicator, either on the engine or off the engine. If the permissible clearance is exceeded, the turbocharger should be reconditioned.
CHECKING SHAFT END CLEARANCEDisassembling The Turbocharger
Compressor Cover and Turbine Housing
With all turbocharger openings covered, wash exterior of the turbocharger thoroughly with a nonflammable fluid before disassembly.Prior to disassembly, mark compressor cover (1), turbine housing (4) and bearing housing (2) to insure correct positioning at assembly.
PREPARING TO REMOVE COMPRESSOR COVER AND TURBINE HOUSING
1-Compressor cover. 2-Bearing housing. 3-Clamps. 4-Turbine housing.
REMOVING NOZZLE
2-Bearing housing. 5-Turbine back plate. 6-Nozzle.
Use caution when removing turbine housing to prevent nozzle (6) from falling.Lift nozzle (6) from turbine back plate (5).
Rotating Parts
Before disassembling the rotating assembly, measure shaft end clearance as previously described. If clearance is excessive, or if either the turbine wheel or impeller has rubbed against the housing or cover, replace the bearings and/or thrust bearing, and thrust rings. Bent impeller blades require replacement of the impeller. Turbine blades, which are noticeably bent require replacement of the turbine and shaft assembly.Bearing failure can damage the shaft journals and/or thrust bearing or rings. Excessive wear or roughness renders the shaft unsuitable for reuse. If the shaft journals measure less than the specified diameter, install a new turbine and shaft assembly. Visual inspection and experience are the only ways to determine when the roughness of shaft prohibits reusing