Yanmar 6LY3 series Service Manual page 300

TROUBLESHOOTING
Trouble symptom
The starting motor rotates but the engine will not start.
No fuel.
Faulty fuel injection nozzle.
Faulty fuel injection pump.
Faulty fuel injection system.
13-10
Causes
The viscosity of the fuel is too
high and the fuel does not
flow.
Fuel line is frozen.
Air in the fuel system.
Fuel filter is clogged.
No fuel in the fuel tank.
A fuel cock is closed.
Clogged fuel system.
Fuel feed pump.
Valve seat.
Needle valve.
Wear of nozzle seat.
Clogged fuel nozzle hole(s).
Nozzle opening pressure.
Wear of plunger.
Plunger spring is broken.
Plunger is stuck.
Delivery valve spring is
broken.
Air in the fuel system.
Injection timing.
Loose fuel injection line.
Damaged fuel injection line.
Air in the fuel injection line.
© 2007 Yanmar Marine International
Troubleshooting by Symptom
Corrective action
Use the recommended fuel.
Warm up the fuel.
Bleed air in the fuel system.
Replace.
Refuel.
Open the fuel cock.
Check the fuel system and
repair if necessary.
Check / repair or replace.
Check the fuel spray
condition. If a malfunction is
found, send to the FIE shop
for service or replace.
Check. If a malfunction is
found, send it to the FIE shop
for service or replace. (If
measuring lag with a YDT,
the movement of rack can be
checked.)
Bleed air in the fuel system.
Check the pump fitting.
Reassemble.
Retighten if necessary.
Replace if necessary.
Bleed air.
6LY3 Service Manual
Remarks
See Fuel Selection on
page 3-6.
See Fuel System on
page 6-1.
See Fuel Filter Components
and Functions on page 6-33.
See Check the Fuel Level on
page 4-6.
See Check the Fuel Level on
page 4-6.
See Fuel Filter Components
and Functions on page 6-33.
See Basic Checkpoints on
page 6-24.
See Fuel Injection Nozzle
Components and Functions
on page 6-26.
See Troubleshooting the
Fuel Injection System on
page 6-24.
See Fuel System on
page 6-1.
See Troubleshooting the
Fuel Injection System on
page 6-24.
See Troubleshooting the
Fuel Injection System on
page 6-24.