JLG E300 Operator Manual - Manual (Page 81)

SECTION 5 - EMERGENCY PROCEDURES
3121214 – JLG Lift – 5-3
5.5 MANUAL DESCENT SYSTEM
The manual descent system is used, in the event of total power
failure or in case the key is not accessible to the ground person-
nel, to lower the upper, lower and jib booms using gravity. To
operate the manual descent system, proceed as follows:
Machines built Prior to S/N 0300063313 and from S/N
0300127575 to Present.
1. Locate the manual descent knob on main valve and turn
(clockwise) to open. Install handle into manual descent
pump and lower the lower boom by pumping the handle
until the boom is completely lowered.
2. Turn manual descent knob (counterclockwise) to close
and lower the upper boom by pumping the handle until
it is completely lowered. Return the manual descent
knob to the center position and stow the handle in
bracket provided.
Machines built from S/N 0300063313 to S/N 0300127575.
1. Locate the manual descent knob on main valve and turn
(counterclockwise) to open. Install handle into manual
descent pump and lower the lower boom by pumping
the handle until the boom is completely lowered.
2. Turn manual descent knob (clockwise) to close and
lower the upper boom by pumping the handle until it is
completely lowered. Return the manual descent knob to
the center position and stow the handle in bracket pro-
vided.
Jib Manual Descent
CRUSHING HAZARD
DO NOT REACH THROUGH THE JIB SECTION TO ACCESS THE KNOB.
ALWAYS ACCESS FROM THE UNDER SIDE OF THE JIB.
Locate the manual descent knob located on the jib cylinder.
Turn the knob counterclockwise until the jib begins to
descend. Return the knob to the closed position (clockwise)
after the jib is completely lowered.
Manual Swing Override
The manual swing override is used to manually swing 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.