JLG 110HX Service Manual - Manual (Page 47)

SECTION 2 - PROCEDURES
3120864 – JLG Lift – 2-23
16. If applicable, install the cartridge-type holding valve
and fittings in the rod port block using new o-rings
as applicable. Torque holding valves in accordance
with Table 2-3.
IF THE CYLINDER IS TO BE TESTED PRIOR TO INSTALLATION ON
THE MACHINE, EXTREME CARE SHOULD BE USED TO INSURE
THAT THE OUTER END OF THE ROD IS SUPPORTED. USE
EITHER A TRAVELING OVERHEAD HOIST, FORKLIFT, OR OTHER
MEANS TO SUPPORT THE OVERHANGING WEIGHT OF THE
EXTENDING ROD.
NOTE: Steps (17) thru (20) apply to the telescope cylinder.
17. Elevate the barrel end of the cylinder to a work
bench or other suitable device.
18. Plug the retract port and supply hydraulic power to
the extend port.
19. Open the bleeder port plug (TP), venting all trapped
air to atmosphere. Retighten the bleeder port plug.
Disconnect the hydraulic power source and remove
plug from retract port.
20. An alternative to steps (18) thru (20) is to position
the barrel horizontally in a suitable holding device,
attach a hydraulic power source to both extend and
retract ports, while supporting the cylinder rod, cycle
the cylinder a minimum of 5 times with the bleeder
port unplugged, venting all trapped air to atmo-
sphere. A suitable hose may be attached to the
bleeder port with the end in a container suitable to
contain the hydraulic fluid. After all air is vented
remove all attached hoses, and install the bleeder
port plug. Also plug the extend and retract ports until
cylinder is installed in boom.
2.12 BOOM MAINTENANCE
Removal
1. Shut down machine systems.
NOTE: Boom Assembly weighs approximately 4536 kg.
2. Using suitable lifting equipment, adequately support
boom weight along entire length of retracted boom.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID ENTRY OF
CONTAMINANTS INTO SYSTEM.
3. Tag and disconnect hydraulic lines that run along
the side of the boom.
4. Remove hardware attaching upper lift cylinder
attach pin to boom.
5. Using a slide hammer or similar tool, and taking care
not to damage pin, remove pin from boom.
6. Using all applicable safety precautions, and only if
necessary, operate crane and fully retract lift cylin-
der.
7. Shut down machine systems.
8. Tag and disconnect all wiring to ground control box.
9. Remove boom length/angle indicator box.
10. Loosen and remove hardware securing boom pivot
pin.
11. Ensuring that boom is adequately supported and
using a suitable slide hammer, carefully remove
pivot pin from boom and turntable structure. Ensure
that boom and turntable structure are not damaged.
12. Carefully lift boom assembly clear of turntable and
lower to ground or suitably supported work surface.
Disassembly
NOTE: Left or right is determined facing the machine from
the platform.
1. Loosen the right side powertrack bracket and pow-
ertrack and lay on top of boom assembly.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID ENTRY OF
CONTAMINANTS INTO SYSTEM.
Table 2-3.Holding Valve Torque Specifications
Description Torque Value
Sun - 7/8 Hex M20 x 1.5 Thds. 41-48 Nm
Sun - 1 1/8 Hex 1/14 UND Thds. 61-68 Nm
Sun - 1 1/4 Hex M36 x 2 Thds. 204-217 Nm
Racine - 1 1/8 Hex 1 1/16 - 12 Thds. 68-75 Nm
Racine - 1 3/8 Hex 1 3/16 - 12 Thds. 102-109 Nm
Racine - 1 7/8 Hex 1 5/8 - 12 Thds. 136-149 Nm