TROUBLESHOOTING
12-6
6LPA Service Manual
Troubleshooting Chart
© 2007 Yanmar Marine International
Failure of governor
Damaged governor bearing
Replace
Faulty operation of governor link
Repair
Sticking governor sleeve
Clean
Fuel control sleeve failure
Disassemble, clean and
service
Other
Overload operation
Reduce load
Moving parts seized
Disassemble, inspect and
conduct servicing
Slippage of clutch
Inspect and repair
Engine stops suddenly:
No fuel feed
Fuel level in fuel tank is low
Add fuel and prime
Air trapped in fuel system or fuel injection
Bleed air
Water trapped in fuel tank
Drain water from drain cock
and fuel pipe, conduct priming
Fuel cock closed
Inspect and repair as
necessary
Clogged fuel filter
Replace
Broken fuel pipe
Replace
Failure of fuel feed pump
Replace
Faulty operation of governor
Broken governor spring
Replace
Sticking governor sleeve
Inspect and repair
Actuated emergency stop
system (NOTE: this section is
not related to the engine)
Loose lubrication oil pressure adjusting valve
Tighten valve
Clogged lubrication oil filter
Clean
Leak from safety valve of lubrication oil pump
Tighten safety valve
Failure of lubrication oil pump
Disassemble and repair, or
replace
Actuated low lubricant pressure relay
Return to the original
operating condition
Actuated over speed relay
Return to the original
operating condition
Actuated water shut-off relay
Return to the original
operating condition
Other
Moving parts seized
Disassemble and repair, or
replace
Overheating caused by insufficient seawater
Overhaul seawater pump and
check for clogged seawater
path
Symptom
Probable Cause
Measure