JLG 460SJ Service Manual - Manual (Page 266)

SECTION 4 - BOOM & PLATFORM
4-2 – JLG Lift – 3120895
a. Disconnect wiring harness from ground control
harness connector.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID ENTRY OF CON-
TAMINANTS INTO SYSTEM.
b. Tag and disconnect hydraulic lines from boom
to control valve. Use a suitable container to
catch escaping hydraulic fluid. Cap all hydraulic
lines and ports.
c. Using a suitable lifting device, adequately sup-
port boom weight along entire length.
NOTE: The 400S boom weighs approximately 985 lbs. (447
kg). The 460SJ boom weighs approximately 1250
lbs. (567 kg).
d. Remove the bolts and keeper pins securing the
lift cylinder pivot pin. Using a suitable brass drift
and hammer, remove the pivot pin from the
lower boom.
e. Remove hardware securing the boom pivot pin.
Using a suitable brass drift and hammer, remove
pin from the turntable.
f. Carefully lift boom assembly clear of turntable
and lower to ground or suitable supported work
surface.
Disassembly
1. Using a portable power source, attach hose to tele-
scope cylinder port block. Using all applicable
safety precautions, activate hydraulic system and
extend cylinder to gain access to cylinder rod retain-
ing pin. Shut down hydraulic system.
2. Carefully disconnect hydraulic hose from retract port
of cylinder. There will be initial weeping of hydraulic
fluid which can be caught in a suitable container.
After initial discharge, there should be no further
leakage from the retract port.
3. Remove hardware securing telescope cylinder to
the fly boom section, then remove pin from fly.
4. Remove hardware securing telescope cylinder to
the base boom section.
5. Using a suitable lifting device, remove telescope cyl-
inder from boom sections.
NOTE: The telescope cylinder weighs approximately 324
lbs. (147 kg).
6. Tag all hoses and wires from front of fly boom and
bottom of base boom for reassembly.
Figure 4-3. Location of Components - Boom Removal