JLG 120HX ANSI Service Manual - Manual (Page 42)

SECTION 2 - PROCEDURES
2-22 – JLG Lift – 3120686
16. Using lightweight motor oil (SAE 20W), adequately
lubricate portion of chain occupying cylinder chain
rest.
17. Using suitable lifting equipment, maneuver tele-
scope cylinder and outer mid section extend chain
assembly into position at aft end of assembled
boom sections.
18. With a slight downward angle on the cylinder, insert
sheave and chain adjust into boom sections until it
is possible to insert chain adjust into attach block at
rear of outer mid section. Temporarily install chain
adjust and locknuts.
19. Carefully feed telescope cylinder approximately half-
way into boom sections, lubricating chain with light-
weight motor oil as it passes along chain rest. Attach
extension bar to chain and continue inserting into
boom sections.
20. Install fly section retract chain sheaves, seals and
thrustwashers at aft end of outer mid section.
21. Install sheave pins and if necessary, tap pins into
place using a soft headed mallet. Secure pins with
setscrews.
22. Install lubrication fittings on ends of pins and lubri-
cate sheaves with MPG.
23. Install fly section retract chains at lower aft end of fly
section. Install chain attach pins and flatwashers and
secure with cotter pins.
24. Carefully place fly section retract chains around
chain sheaves at aft end of inner mid section and
through bottom of inner mid section.
25. Install fly section retract chain clevis into attach
block at lower front end of inner mid section. Install
adjust nut and locknut on clevis.
26. Install outer mid section retract chain sheaves and
thrust washers at aft end of inner mid section.
27. Install sheave pins and, if necessary, tap pins into
place using a soft headed mallet. Secure pins with
setscrews.
28. Install lubrication fittings on ends of pins and lubri-
cate sheaves with MPG.
29. Install outer mid section retract chains at lower aft
end of outer mid section. Install chain attach pins
and flatwashers and secure with cotter pins.
30. Carefully place outer mid section retract chains
around chain sheaves at aft end of inner mid sec-
tion. Tie chains to underside of inner mid section
using suitable straps.
31. Using suitable lifting equipment, carefully align holes
in telescope cylinder trunnion and holes in aft end of
inner mid section.
32. Install trunnion pins, ensuring that holes in pins align
with holes in trunnion. If necessary, tap pins into
place with a soft headed mallet. Secure pins with
setscrews.
33. Using suitable lifting equipment, carefully slide
assembled inner mid, outer mid, and fly sections
into base section.
34. As sections are being installed, remove straps from
outer mid section retract chains and feed attach cle-
vis through holes in bottom of forward end of base
section.
35. Install outer mid section retract chain clevis into
attach block at lower front end of base boom sec-
tion. Install adjust nut and locknut on clevis.
NOTE: When installing base section wear pads, install same
number and thickness of shims as were removed
during disassembly.
36. Install base section top front wear pads and shims,
as required, using bolts and lockwashers.
37. Install base section lower front wear pads, mounting
blocks, and shims, as required, using bolts, wash-
ers, and lockwashers.
38. Install base section side front wear pads and shims,
as required, using bolts and lockwashers.
39. Carefully align telescope cylinder rod end with holes
in aft end of base boom section and install attach
pin. If necessary, tap pin into place using a soft
headed mallet. Secure pin with cotter pins.
40. Install outer mid section extend chain attach block at
aft end of base section and secure with bolts and
lockwashers.
41. Install outer mid section extend chain clevis through
hole in attach block and secure with adjust nut and
locknut.
42. Attach platform to boom assembly.
43. Attach the left side powertrack to boom assembly.
44. Connect wiring to consolette box.
45. Connect hydraulic lines to slave level cylinder and
rotator motor.
46. Attach the right side powertrack bracket and power-
track to boom assembly.
Installation
1. Using suitable lifting equipment, position assembled
boom on turntable so that boom pivot holes in both
boom and turntable are aligned.