Oshkosh Corporation JLG 450AJ, Service And Maintenance Manual

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SECTION 4 - BOOM & PLATFORM
3121659 – JLG Lift – 4-7
Inspection
1. Inspect all boom pivot pins for wear, scoring or other
damage, and tapering or ovality. Replace pins as
needed.
2. Inspect lift cylinder pins for wear, scoring or other dam-
age, and for tapering or ovality. Ensure pin surfaces are
protected prior to installation. Replace pins as needed.
3. Inspect telescope cylinder rod attach pin for wear, scor-
ing or other damage. Replace pin as needed.
4. Inspect inner diameter of boom pivot bushings for scor-
ing, distortion, wear or other damage. Replace bushings
as needed.
5. Inspect wear pads for wear.
6. Inspect all threaded components for damage such as
stretching, thread deformation, or twisting. Replace as
needed.
7. Inspect structural units of boom assembly for bending,
cracking, separation of welds, or other damage. Replace
boom sections as needed.
Main Boom Assembly
1. Install power track to the attach point on the base boom
section. Secure power track with the attaching hard-
ware.
2. Install hydraulic lines and electrical cables in power
track.
3. Install wear pads to the aft end of the fly section.
4. Using suitable lifting equipment, slide fly section into
the base section until power track attach point aligns
with holes in side of base section.
5. Attach power track to aft end of fly boom section.
Secure power track with attaching hardware.
6. Using suitable lifting equipment, slide fly boom section
out to gain access to telescope cylinder attach pin hole.
7. Measure distance between telescope cylinder port
block attach point on base boom section and attach
point on fly boom section.
8. Connect a suitable auxiliary hydraulic power source to
telescope cylinder port block.
9. Extend telescope cylinder the distance of the two attach
points.
10. Secure sling and lifting device at telescope cylinder’s
approximate center of gravity. Lift cylinder to aft end of
boom assembly.
WHEN INSERTING TELESCOPE CYLINDER INTO BOOM, CARE MUST BE TAKEN
NOT TO DAMAGE POWER TRACK ASSEMBLY.
11. Slowly slide telescope cylinder into boom assembly
Align rod end with attach point in fly section. Insert pin
and secure with retaining ring.
12. Align bolt holes at aft end of base boom section with
telescope cylinder port block. Secure telescope cylinder
with hardware.
13. Install wear pads at end of base boom section. Using
shims, adjust adjustable wear pads to zero clearance.
Adjust pads alternately side to side, so fly boom section
is centered in base boom section.
14. Retract boom section fully. Using shims, adjust wear
pads at aft end of boom section to zero clearance.
Adjust pads alternately side to side, so fly boom section
is centered in base boom section.
15. Disconnect auxiliary power source from telescope cylin-
der.