JLG 600SC_660SJC Service Manual - Manual (Page 96)

SECTION 5 - HYDRAULICS
5-10 – JLG Lift – 3120898
4. Install extend cable mounting blocks to threaded
ends of cables. Loosely install nuts and jam nuts
onto the threaded ends of cables.
NOTE: When installing cables, care must be taken not to
twist or cross the cables.
5. 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: DAMAGE TO COMPONENTS
MAY RESULT FROM FORCIBLE IMPACT WITH THESE ASSEM-
BLIES.
6. Carefully install the telescope cylinder barrel end
support into slots in mid boom and secure with
blocks and bolts. Use Loctite #242 on bolts.
7. Align holes in aft end of the fly boom section with
holes in cable mounting block, then secure with
mounting hardware.
8. Align holes in aft end of the base boom section with
holes in cable mounting block, then secure with
mounting hardware.
9. Remove cylinder port plugs and hydraulic line caps
and correctly attach lines to cylinder ports.
10. Align holes in rod end of the telescope cylinder with
holes in push bar. Install push bar pin and secure
with mounting hardware.
11. Align holes in push bar with holes in turntable. Install
push bar pin and secure with mounting hardware.
NOTE: Boom cables must be torqued after installation of the
telescope cylinder. (See Section 4 - Boom & Plat-
form)
Main Boom Lift Cylinder Removal
1. Place the machine on a flat and level surface. Start
the engine and place the main boom in the horizon-
tal position. Shut down engine and prop the boom.
(See Figure 5-14., Boom Positioning and Support,
Cylinder Repair)
2. Remove the hardware retaining the cylinder rod
attach pin to the boom. Using a suitable brass drift,
drive out the cylinder rod attach pin.
3. Using auxiliary power, retract the lift cylinder rod
completely.
4. Disconnect, cap and tag the main boom lift cylinder
hydraulic lines and ports.
5. Remove barrel end attach pin retaining hardware.
Using a suitable brass drift drive out the barrel end
attach pin from the turntable.
6. Remove the cylinder from the turntable and place in
a suitable work area.
Main Boom Lift Cylinder Installation
1. Install lift cylinder in place using suitable slings or
supports, aligning attach pin mounting holes on the
turntable.
2. Using a suitable drift, drive the barrel end attach pin
through the mounting holes in the lift cylinder and
the turntable. Secure in place with the pin retaining
hardware.
3. Remove cylinder port plugs and hydraulic line caps
and correctly attach lines to cylinder ports.
4. Using auxiliary power, extend the cylinder rod until
the attach pin hole aligns with those in the boom.
Using a suitable soft mallet, drive the cylinder rod
attach pin through the boom and lift cylinder. Secure
the pin in place with attaching hardware.
5. Remove boom prop and overhead crane. Activate
hydraulic system.
6. Using all applicable safety precautions, operate the
boom functions. Check for correct operation and
hydraulic leaks. Secure as necessary.
7. Check fluid level of hydraulic tank and adjust as nec-
essary.