8. Fuel system
134
5. Excessive engine smoke
and knoc
king
• Defective injection timing
• Too low nozzle injection pressure
• Broken nozzle spring
• Nozzle not working properly
• Excessively work plunger
• Defective delivery valve seat
• Excessive fuel supply
•Adjust
•Adjust
• Replace it
• Replace it
•Adjust
• Replace it
• Check feed pump
6.
Unstable engine power
• Insufficient fuel supply
• Air entered into fuel
• Water entered into fuel
• Defective plunger operation
• Defective actuator operation
• Defective nozzle
• Injection start pressure different between cylinders
• Defective controller
• Check feed pump
• Air bleeding
• Replace fuel
• Disassemble / correct
• Disassemble / correct
• Disassemble / correct
•Adjust
•Adjust
7. Engine cannot reach t
he
m
ax. speed
• Nozzle not working properly
• Defective operation of actuator or controller
• Disassemble / correct
•Adjust
8.
Unst
able engine idling
• Defective controller operation
• Defective plunger operation
• Defective magnetic pickup sensor
•Adjust
• Disassemble / correct
• Inspect or replace
Symptom Causes Troubleshooting