JLG 660SJ ANSI Service Manual - Manual (Page 119)

SECTION 3 - CHASSIS & TURNTABLE
3120718 – JLG Lift – 3-65
2. Check the Spark Plugs for presence of spark. If
there is no spark at the plugs during cranking:
a. Overspeed relay not activating.
b. Check the ignition module red/green wire for 12
volts.
c. Check the white/black wire coming from the 8-
pin connector (pin-H) that runs to the overspeed
relay on terminal 85 for proper ground.
3. Ignition module may have failed.
a. Ignition module series: AA, AB and FA prior to
date code-1889 may need replaced. (refer to:
Ford Technical Bulletin # FF-91-99)
b. Check the vacuum advance tube attached to the
ignition module for secure connection.
Try to start the engine.
Checking the Fuel
The engine may not be getting fuel to the carburetor
1. Check the fuel shutoff solenoid
a. Must have 12 volt while cranking the engine.
2. Check the electric fuel pump
a. Must have 12 volts or be able to hear the pump
running while cranking the engine.
b. Check fuel pressure, must have a minimum of
2-4lbs.
3. Check Fuel Filter:
NOTE: Some JLG machines have a fuel return line between
the fuel pump and carburetor, if this return line is
pinched and the fuel pressure increases this indi-
cates a clogged fuel filter.
4. Check the fuel pump supply line for any obstruction.
Try to start the engine.
NOTE: JLG Industries Inc. recommends the use of engine
block heaters and or cold weather packages for
machines intended for use in 0° F (-18° C) or colder
conditions. Refer to the JLG Parts Manual for specify
options for your machine.
(Machines equipped with non-hydrostatic gear pump
or non-proportional drive systems, i.e. H models,
60HA should consider having block heaters and or
cold weather packages installed for use in 20° F (-
6.5° C) and colder conditions.
3.22 GLOW PLUGS
If the glow plug option is enabled in the JLG Control Sys-
tem, the glow plug and indicator lamp will be energized
when the Power/Emergency Stop switch is pulled on if the
ambient air temperature is less than 50° F (10° C) and the
engine coolant temperature is less than 140° F (60° C).
This determination will occur one second after the Power/
Emergency Stop switch has been pulled on. The lamp
and glow plugs will remain energized for the period of
time specified by the setting in the JLG Control System.
Engine start shall be disabled during this period. On Deutz
engines, the glow plugs will continue (post glow) after the
engine has started for three times the machine digit set-
ting.