Yanmar 4LHA-HTP - Page 502

Chapter 4 Intake and Exhaust System
4. Turbocharger
4LHA Ser
4-9-6 Abnormal sound or vibration
<Abnormal sound>
Possible cause
Corrective action
1) Excessively narrowed gas path due to
clogged nozzle in turbine housing or
reverse flow of blower discharge during
acceleration (generally called surging)
2) Contacting rotating parts
• Disassemble and wash the turbocharger.
• Disassemble and repair or replace the
turbocharger.
<Abnormal vibration>
Possible cause
Corrective action
1) Loose intake, exhaust or oil pipe
connection with the turbocharger
2) Chipping of turbine wheel or compressor
impeller caused by contacting between
rotating part and adjacent parts due to
damaged bearing, or invasion by foreign
matter
3) Unbalanced rotating part
• Check pipe connections of the
turbocharger and repair as needed.
• Disassemble and repair or replace the
turbocharger. If foreign matter has
invaded, completely remove it.
• Repair or replace the rotating part.
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