Yanmar 6LPA-STP2 Service Manual page 315

Troubleshooting Chart
12/05
Symptom
Excessive quantity of fuel is
injected
Other
Breakdown of turbocharger:
Drop in intake pressure
Increased intake pressure
6LPA Service Manual
Probable Cause
Excessive delivery from fuel injection pump
Insufficient seawater
Piston clearance excessive
Bearing clearance excessive
Improper fuel
Water trapped in fuel
Poor compression
Dirty air filter
Dirty guide vane at outlet of compressor
Leak from intake piping
Leak of exhaust gas
High intake air temperature
Drop in air pressure in engine room
Broken seal ring
Broken turbine impeller
Broken nozzle ring
Dirty turbine impeller
Clogged nozzle
Clogged exhaust pipe
Incorrect reading of pressure gage
Exhaust gas leak
Failure in fuel injection system
Deformed turbine nozzle
Dirty turbine side
Increase in load (overloading)
Incorrect reading of pressure gage
© 2007 Yanmar Marine International
TROUBLESHOOTING
Measure
Re-adjust fuel injection pump
Replace seawater pump
impeller
Replace
Replace
Replace with correct fuel
Replace fuel
Inspect and service
Clean
Clean
Repair
Repair
Complete thermal insulation
of exhaust pipe
Ensure intake air path is
unrestricted from outside air.
Clean air cleaner
Ensure intake air path is
unrestricted from outside air.
Replace
Replace
Replace
Clean
Clean
Clean
Replace
Re-mount of turbocharger
Inspect and adjust the
injection timing
Overhaul injection pump,
repair or replace any
defective parts
Disassemble and inspect
injection valve, repair or
replace any defective parts
Replace
Clean
Reduce load
Replace
12-9