JLG X20JP - X600AJ Service Manual - Manual (Page 164)

SECTION 4 - BOOM & PLATFORM
3121623 – JLG Lift – 4-11
8. Properly position the retraction wire rope sheaves
assemblies at the rear end of the mid boom section;
ensure all sheave-to-mounting block attachment
holes align. Install the sheave pins and secure them
with mounting hardware. Position retract wire ropes
onto the sheaves.
9. Install sheave guards to rear end of mid boom sec-
tion and secure with mounting hardware.
10. Slide mid boom section into the base boom section.
Allow the retraction wire ropes to trail between the
bottom surfaces of boom sections. Adjust boom, if
necessary, for a total of 1/16 inch (0.062) clearance.
11. Install wear pads into the forward position of the
base boom section. Adjust boom, if necessary, for a
total of 2/10 inch (0.20) clearance.
12. Install sheave block to bottom of base boom section
and adjust block so that retract wire ropes do not
come into contact with boom surfaces.
13. Install wire rope threaded ends thru attachment
holes in the bottom of base boom section. Loosely
install nuts and jam nuts onto the threaded ends of
wire ropes.
14. Pull the boom sections out to approximately where
they were extended to for telescope cylinder
removal.
15. Install a new extend sheave on the end of the tele-
scope cylinder.
16. Route new extend cables around the telescope cyl-
inder. Loosely fasten the threaded end of the cables
to the rod end of the telescope cylinder with the
adjusting nuts and lock nuts. Install the opposite
end of the cables in the cable mount block.
17. Use tape or tie straps to fasten the cables to the tele-
scope cylinder assembly. It is important that the tape
or straps be strong enough to hold the cable in
place yet weak enough to break and fall away when
the cables are adjusted.
WHEN PUSHING THE TELESCOPE CYLINDER INTO THE BOOM, IT
MAY BE NECESSARY AT SOME POINT TO TURN THE CYLINDER
SLIGHTLY IN ORDER TO CLEAR ASSEMBLIES MOUNTED WITHIN
THE BOOM. CARE MUST BE TAKEN TO MOVE THE CYLINDER
SLOWLY INTO THE BOOM. DAMAGE TO COMPONENTS MAY
RESULT FROM FORCIBLE IMPACT WITH THESE ASSEMBLIES.
NOTE: The telescope cylinder weighs approximately 600 lbs.
(275 kg).
18. Using adequate lifting equipment, carefully push the
telescope cylinder assembly and cables back into
the boom.
19. Apply Loctite #242 to the bolts and fasten the tele-
scope cylinder rod to the boom base section with
the bolts, shims, mounting blocks.
Figure 4-16.
20. Apply Loctite #242 to the bolts and fasten the tele-
scope cylinder barrel to the boom mid section with
the bolts, shims, mounting blocks.
Figure 4-17.
21. Using a 3/8 drive extension approximately 4 feet (1.2
m) long, install the bolts and washers securing the
cable mount block to the boom fly section. Tape the
bolts to the socket at the end of the extension to pre-