JLG 80HX_HX+6_HXER ANSI Service Manual User Manual
Page 81
SECTION 4 - BOOM & PLATFORM
3120271
– JLG Lift –
4-1
SECTION 4. BOOM & PLATFORM
4.1
BOOM MAINTENANCE
Removal
1.
Remove the platform from the boom assembly.
2.
Remove the slave leveling cylinder from the boom
assembly.
NOTE: The boom assembly weighs approximately 4800 lbs.
(2200 kg).
3.
Using suitable lifting equipment, adequately support
the boom weight along the entire length of the
retracted boom.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
4.
Tag and disconnect the hydraulic lines that run
along the side of the boom.
5.
Remove the hardware attaching the upper lift cylin-
der attach pin to the boom.
6.
Using a slide hammer or similar tool, and taking care
not to damage the pin, remove the pin from the
boom.
7.
Using all applicable safety precautions, and only if
necessary, operate the crane and fully retract the lift
cylinder.
8.
Shut down all machine systems.
9.
Tag and disconnect all wiring to the ground control
box.
10.
Loosen and remove the hardware securing the
boom pivot pin.
11.
Ensuring that the boom is adequately supported
and using a suitable slide hammer, carefully remove
the pivot pin from the boom and turntable structure.
Ensure the boom and turntable structure are not
damaged.
12.
Carefully lift the boom assembly clear of the turnta-
ble and lower to the ground or suitably supported
work surface.
Disassembly
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING THE LINES TO AVOID ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
1.
Remove all hydraulic lines, electrical cables, carrier
tube, and power track from the right side of the
boom assembly.
2.
Remove control console from the platform.
3.
Remove the platform from the fly boom assembly.
4.
Remove the carrier tube and power track from the
right side of the boom assembly.
5.
Remove and disassemble the extension chain
attachment and adjustment assembly (mounted at
aft of boom base section) as follows:
a. Remove the jam nut and nut which secures the
chain attachment clevis bolt to the chain adjust-
ment block.
b. Remove the bolts and washers which secure the
extension chain attachment assembly to the
base boom section; remove the chain attach-
ment assembly from the base boom section
mounting point.
c. Remove the cotter pins from the clevis pins.
Remove the clevis pins and washers from the
chain attachment clevis bolt; remove the chain
attachment clevis from the chain.
6.
Remove and disassemble the retraction chain
attachment and adjustment assembly as follows:
a. Remove the nuts and washers from the chain
attachment shield, and remove the shield from
the boom base section.
b. Remove the jam nut and nut from the threaded
end of the tension-adjusting clevis bolt. Remove
the entire tension-adjusting assembly from the
boom-mounted bracket.
c. Remove the cotter pins from the clevis pins
which secure the retraction chains to the clevis
bolt assembly.
d. Remove the cotter pins, nuts and bolts securing
the chain attach blocks to the clevis bolt assem-
bly. Remove the attach blocks.
e. Separate the top and bottom clevis bolt assem-
bly plates. Remove the clevis bolt from the bot-
tom plate.