Platform Or Boom Caught Overhead; Auxiliary Descent System; Manual Swing Override - JLG 340AJ Operation And Safety Manual

SECTION 5 - EMERGENCY PROCEDURES

Platform or Boom Caught Overhead

If the platform or boom becomes jammed or snagged in over-
head structures or equipment, rescue platform occupants 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 low-
ered in the event of primary power (engine power) loss. This sys-
tem 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 normally 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 con-
trol switch for the desired function.
5-2
If it is necessary to raise the jib in order to properly perform the
auxiliary descent procedure, use the following procedure.
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 operate 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.
– JLG Lift – 3121258