JLG 340AJ Operator Manual - Manual (Page 78)

SECTION 5 - EMERGENCY PROCEDURES
5-2 – JLG Lift – 3121258
Platform or Boom Caught Overhead
If the platform or boom becomes jammed or snagged in
overhead structures or equipment, rescue platform occu-
pants prior to freeing the machine.
5.4 AUXILIARY DESCENT SYSTEM
Refer to Figure 5-1., Auxiliary Descent Decal and Hand Pump.
The auxiliary descent system allows the boom and jib to be
lowered in the event of primary power (engine power) loss.
This system uses electrically powered solenoid valves and
the force of gravity to lower the booms and jib. The following
functions are included in this system and will operate nor-
mally if the engine is not running and the auxiliary power
switch has been activated.
• Main Lift Down
• Tower Lift Down
• Jib Lift Down
1. From the ground control console, place the Platform/
Ground Select switch in the Ground position.
2. Pull out the Power/Emergency Stop control.
3. Hold down the Auxiliary Descent Enable Switch and the
control switch for the desired function.
If it is necessary to raise the jib in order to properly perform
the auxiliary descent procedure, use the following proce-
dure.
1. From the ground control console, place the Platform/
Ground Select switch in the Ground position.
2. Pull out the Power/Emergency Stop control.
3. Hold down the Auxiliary Descent Enable Switch, hold up
the jib lift control switch and operate the hand pump
located next to the hydraulic tank to raise the jib.
5.5 MANUAL SWING OVERRIDE
The manual swing override is used to manually swing the boom
and turntable assembly in the event of a total power failure when
the platform is positioned over a structure or obstacle. To oper-
ate the manual swing override, proceed as follows:
1. Using a 7/8 inch socket and ratchet wrench, locate nut
on swing worm gear on left side of machine.
2. Install wrench on nut and ratchet in the direction
desired.