JLG 80HX_HX+6_HXER Service Manual - Manual (Page 28)

SECTION 2 - PROCEDURES
2-6 – JLG Lift – 3120863
2.6 BOOM CHAINS (SEE FIGURE 2-2.)
Adjusting Procedures
ENSURE THE MACHINE IS ON A FIRM AND LEVEL SURFACE.
1. Fully retract the boom in the horizontal position (±
5°) with no load in the platform.
2. Extend the platform approximately 1 meter (3 ft.).
3. Torque the boom retract chain adjuster to 69 NM (50
ft. lbs.), then torque the boom extend chain adjuster
to 69 NM (50 ft. lbs.).
4. Retract the platform approximately 0.3 m (1 ft.).
5. Check the boom extend chain adjusters (69 NM {50
ft. lbs.} required).
6. Retract the platform approximately 0.3 m (1 ft.) once
again.
7. Recheck the extend chain adjusters (69 NM {50 ft.
lbs.} required).
8. Extend the platform approximately 0.3 m (1 ft.).
Check for proper operation of boom.
9. Recheck the retract chain adjuster torque. (69 NM
{50 ft. lbs.} required).
10. Fully extend and retract the boom and check for
proper operation.
JLG Industries, Inc. requires a complete boom disassem-
bly, per instructions outlined in Section 2.12, Boom Main-
tenance, every two years. All boom chains and related
components (i.e., sheaves, pins, sprockets, wear pads,
etc.) must also be inspected and replaced (as necessary)
during this disassembly.
An immediate disassembly of the boom assembly and
inspection of the boom chains and related components is
required if any of the following conditions occur:
1. After the machine is exposed to hostile environ-
ments or conditions (i.e. extreme cold, dust, sand,
blasting grit, salt, chemicals, etc.), which could
adversely affect boom operation.
2. Erratic boom operation or unusual noise exists. See
the Troubleshooting section in this Service Manual.
3. Chain adjustment is required more often than speci-
fied in the Preventive Maintenance and Inspection
Schedule in this Service Manual or links need to be
removed (chain shortened) to make the proper
adjustment.
4. The machine is idle for an extended period (6
months or longer.)
5. The boom is overloaded or sustained a shock load.
Figure 2-2. Typical Boom Assembly