JLG 80HX_HX+6_HXER ANSI Service Manual - Manual (Page 85)

SECTION 4 - BOOM & PLATFORM
3120271 – JLG Lift – 4-5
14. Inspect structural units of the boom assembly for
bending, cracking, separation of welds, or other
damage. Replace boom sections as necessary.
Assembly
NOTE: When installing fly section wear pads, install the
same number and thickness of shims as were
removed during disassembly.
1. Measure the inside dimensions of the base and mid
sections to determine the number of shims required
for proper lift.
2. Install side wear pads to the aft end of the fly sec-
tion; shim evenly to the measurements of the inside
of the mid section.
3. Install the side wear pads to the aft end of the mid
section; shim evenly to the measurement of the
inside of the base section.
4. Shim the insides of the boom sections for a total of
1/16 inch (.062) clearance (if the action is centered,
there will be 1/32 clearance on each side).
5. Slide the fly section into the mid section a distance
of approximately one foot; take the measurement of
the inside of the mid section top wear pad clearance
and fabricate shim packs.
6. Remove the fly section from the mid section and
install two top wear pads and a shim pack. Shim the
top of the fly section for a total of 1/16 inch (.062)
clearance.
7. Slide the mid section into the base section a dis-
tance of approximately one foot; take the measure-
ment of the top wear pad clearance and fabricate
shim packs.
8. Remove the mid section from the base section and
install two top wear pads and a shim pack. Shim the
top of the mid section for a total of 1/16 inch (.062)
clearance.
9. Attach the extension chain to the appropriate clev-
ised attachment point of the chain block weldment
by installing the clevis pin and washer through the
attach holes; secure the clevis pin with a new cotter
pin. Place the chain block weldment in position at
the aft end of the fly section; secure the weldment by
installing the bolts and washers.
WHEN ASSEMBLING BOOM SECTIONS, ENSURE THE BOOM
SLIDING TRAJECTORIES HAVE BEEN CLEARED OF CHAINS,
TOOLS, AND OTHER OBSTRUCTIONS.
10. Slide the fly section into the mid section. Shim the
boom, if necessary, for a total of 1/16 inch (.062)
clearance.
11. Install wear pads into the forward portion of the mid
section. Shim the boom, if necessary, for a total of 2/
10 inch (.20) clearance.
12. Align the attach points of the retraction chains with
those of the chain attachment block, located at the
aft end of the fly section. Install the clevis pins and
washers through the attaching holes of the chains
and block; secure the clevis pins by installing new
cotter pins.
13. Properly position the retraction chain sheave assem-
blies at the aft end of the mid section; ensure all
sheave-to-mounting block attachment holes align.
Install the sheave pin and secure by installing the
setscrews. Position the retraction chains onto the
sheaves.
14. Align the telescope cylinder base-to-sheave attach-
ment points. Install the sheave pin through the cylin-
der base and sheave assembly; secure the pin with
bolt and washer.
15. Secure the sling and lifting device at the telescope
cylinder’s approximate center of gravity, and lift the
cylinder to the aft end of the boom assembly.
WHEN INSERTING THE TELESCOPE CYLINDER INTO THE BOOM,
IT MAY BE NECESSARY AT SOME POINT TO TURN THE CYLIN-
DER SLIGHTLY IN ORDER TO CLEAR ASSEMBLIES MOUNTED
WITHIN THE BOOM. CARE MUST BE TAKEN TO MOVE THE CYL-
INDER SLOWLY INTO POSITION AS DAMAGE TO COMPONENTS
MAY RESULT FROM FORCIBLE IMPACT WITH THESE ASSEM-
BLIES.
16. Position the free end of the extension chain around
and over the sheave. Slowly slide the cylinder into
the boom while maintaining tension on the chain.
(This will keep the chain properly seated in the
sheave groove throughout installation).
17. Align the cylinder base-end attachment holes with
the boom mid section attachment holes; install the
trunnion pins and secure the pins by installing bars,
washers and bolts.
18. Slide the mid section into the base section. Allow the
retraction chains to trail between the bottom sur-
faces of boom sections. Ensure that no twists exist
in the chains. Shim the top of the mid section for a
total of 1/16 inch (.062) clearance.
19. Install wear pads into the forward portion of the base
section. Shim the boom, if necessary, for a total of 2/
10 inch (.20) clearance.
20. Assemble the extension chain attachment and
adjustment assembly (mounted at aft of boom base
section) as follows:
a. Align the attaching holes of the chain attach-
ment clevis bolt with those of the extension