6.4.7. Diagnostics and troubleshooting - 168 - MAINTENANCE OF MAJOR COMPONENTS Complaints Possible causes Corrections 1. Excessive black smoke 1) Air cleaner element clogged 2) Restrictions in air duct 3) Leakage at intake manifold 4) Turbocharger seized up and not rotating 5) Turbine blades and compressor blades coming in contact with each other or damaged 6) Exhaust piping deformed or clogged Replace or clean Check and correct Check and correct Disassemble/repair or replace Disassemble/repair or replace Check and correct 2.
Excessive white smoke 1) Oil leak into turbine and compressor 2) Worn or damaged seal ring due to excessive wear of bearing Disassemble/repair or replace Disassemble/repair or replace 3. Low engine output 1) Gas leak at each part of exhaust system 2) Air cleaner element restricted 3) Turbocharger fouled or damaged 4) Leakage at discharge port on compressor side Check and correct Replace or clean Disassemble/repair or replace Check and correct 4. Unusual sound or vibration 1) Rotor assembly coming in contact 2) Unbalanced rotation of rotor 3) Seized up 4) Each joint loosened Disassemble/repair or replace Disassemble/repair or replace Disassemble/repair or replace Check and correct