Troubleshooting Chart - Yanmar 6LPA-STP2 Service Manual

TROUBLESHOOTING
INTRODUCTION
This section contains information and diagnostic
troubleshooting charts to accurately diagnose and
engine, starter, or alternator problem.

TROUBLESHOOTING CHART

Symptom
Engine does not start or starts with difficulty:
Pinion gear does not engage
Pinion gear is engaged with
ring gear, but does not rotate
No fuel injection
Failure of fuel injection valve
12-4
Probable Cause
Loose terminal of battery / engage magnet
Poor contact of starting switch
Open coil of magnet switch
Rough operation of shifter
Burr at gear tooth tip
Poor clearance between pinion and ring gear
Damaged starter bearing
Loose battery / starter terminal
Poor contact of engage magnet switch
Worn brush
Dirty or rough surface of rectifier
Open circuit of starter coil
Worn rectifier
Slippage of starter / clutch
Excessive resistance of cable between battery and starter
Insufficient battery charge
Incomplete priming of fuel system
Fuel shut-off by faulty speed adjusting system
Clogged fuel inlet filter
Fuel level in fuel tank is low
Closed cock of fuel tank
Clogged fuel pipe
Failure of fuel feed pump
Faulty valve seat
Sticking of nozzle
Worn nozzle
Clogged injection hole
Drop in injection pressure
© 2007 Yanmar Marine International
Introduction
Measure
Tighten
Correct with sandpaper or
replace
Replace
Correct with sandpaper and
apply grease
Correct
Correct
Replace
Tighten
Correct with sandpaper
Replace
Correct with sandpaper #500
to #600
Replace
Replace
Replace
Increase the cable size or
shorten
Charge
Carry out sufficient priming
Re-adjust
Replace
Add fuel
Open cock
Clean
Overhaul or replace
Replace
Replace
Replace
Replace
Re-adjust
6LPA Service Manual