JLG 660SJ Service Manual - Manual (Page 111)

SECTION 4 - BOOM & PLATFORM
3120840 – JLG Lift – 4-9
12. Remove hardware which secures the wear pads to
the aft end of mid boom section; remove the wear
pads from the top, sides and bottom of the mid
boom section.
13. Remove hardware which secures the sheave guards
and sheave assemblies to mid boom section,
remove sheave assemblies from mid boom section.
14. Remove hardware which secures the wear pads to
the front of mid boom section; remove wear pads
from the top, sides and bottom of the mid boom sec-
tion.
15. Using an overhead crane or suitable lifting device,
remove fly boom section from mid section. Note:
When removing fly boom section from mid boom
section, retract wire rope must be dragged along
with fly boom section.
16. Remove hardware which secures the wear pads to
the aft end of fly boom section; remove wear pads
from the top, sides and bottom of the fly boom sec-
tion.
17. When removing wire rope from fly boom section,
push the cable into fly boom. Route wire rope back
through holes in the side of the fly boom section.
Inspection
NOTE: When inspecting pins and bearings Ref. to section 2
General.
1. Inspect all sheaves (extend and retract wire ropes
and telescope cylinder) for excessive groove wear,
burrs or other damage. Replace sheaves as neces-
sary.
NOTE: To check the size, contour and amount of wear, a
groove gauge is used. Replace the sheave if worn as
shown in the following drawing.
2. Inspect extend and retract wire rope sheave bear-
ings for wear, scoring, or other damage, and for
ovality.
3. Inspect extend wire rope and retract wire rope
sheave pins for scoring, tapering and ovality.
Replace pins as necessary.
4. Inspect telescope cylinder sheave pin for scoring,
tapering and ovality. Replace pins as necessary.
5. Inspect boom pivot pin for wear, scoring, tapering
and ovality, or other damage. Replace pins as nec-
essary.
6. Inspect telescope cylinder attach point for scoring,
tapering and ovality. Replace pins as necessary.
7. Inspect upper lift cylinder attach pin for wear, scor-
ing, tapering and ovality, or other damage. Ensure
pin surfaces are protected prior to installation.
Replace pins as necessary.
Figure 4-12. Disassembly Wire Rope Routing Procedure
Figure 4-13. Dimension of Sheaves When New