0389484 JOHNSON CYLINDER AND CRANKCASE ASSY

Failure of turbocharger bearings and seals can cause large quantities of oil to enter the air inlet and exhaust systems. Loss of engine lubricant can result in serious engine damage.Minor leakage of a turbocharger housing under extended low idle operation should not cause problems as long as a turbocharger bearing failure has not occurred.When a turbocharger bearing failure is accompanied by a significant engine performance loss (exhaust smoke or engine rpm up at no load), do not continue engine operation until the turbocharger is repaired or replaced.
An inspection of the turbocharger can minimize unscheduled downtime. An inspection of the turbocharger can also reduce the chance for potential damage to other engine parts.Note: Turbocharger components require clearances that are precise. Severe service applications can accelerate the wear of the components. Severe service applications may require more frequent inspections of the turbocharger.Refer to Table 1 for the Maintenance Intervals of the Napier turbocharger.
Table 1
Maintenance Intervals for Napier Turbochargers
Operating Hours Maintenance Program
Initial 100 Service Hours Confirm the circulation of the turbocharger oil supply. Inspect connections of gas and air pipes for tightness. Inspect the hold down bolts and nuts on the turbocharger housing for tightness.
12000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Rebuild the turbocharger cartridge.
24000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Check the balance of the rotor assembly. Rebuild the turbocharger cartridge.
36000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Replace the turbocharger nozzle and the turbocharger insert assembly. Rebuild the turbocharger cartridge.
48000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings, and bearings. Also, replace the thrust collar, and the turbocharger impeller. Replace the inlet casing of the turbocharger and the outlet casing of the turbocharger. If necessary, replace the bearing housing. Check the balance of the rotor assembly. Rebuild the turbocharger cartridge.
60000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Rebuild the turbocharger cartridge.
72000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Check the balance of the rotor assembly. Rebuild the turbocharger cartridge.
84000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Rebuild the turbocharger cartridge.
96000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings, and bearings. Also, replace the thrust collar, and the turbocharger impeller. Replace the inlet casing of the turbocharger and the outlet casing of the turbocharger. If necessary, replace the bearing housing. Check the balance of the rotor assembly. Rebuild the turbocharger cartridge.
108000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Rebuild the turbocharger cartridge.
120000 Service Hours Remove the turbocharger cartridge. Disassemble the cartridge, and clean the cartridge. Then, inspect the cartridge. Replace oil seal rings and bearings. If necessary, replace the bearing housing. Replace the thrust collar. Check the balance of the rotor assembly. Rebuild the turbocharger cartridge.