JLG 601S Service Manual - Manual (Page 158)

SECTION 5 - HYDRAULICS
5-8 – JLG Lift – 3120866
5.5 CYLINDER REMOVAL AND
INSTALLATION
Main Boom Telescope Cylinder Removal
1. Place machine on a flat and level surface, with main
boom in the horizontal position.
2. Shut down engine. Support main boom basket end
with a prop.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDI-
ATELY AFTER DISCONNECTING LINES TO AVOID THE ENTRY OF
CONTAMINANTS INTO THE SYSTEM.
3. Tag and disconnect hydraulic lines to telescope cyl-
inder. Use a suitable container to retain any residual
hydraulic fluid. Cap hydraulic lines and ports.
4. Remove the hardware securing cover plate on bot-
tom of the base boom section and remove cover.
NOTE: Do not allow cable to rotate. This may damage the
cable.
5. Clamp both threaded ends of cable to prevent rota-
tion. Note: Do not clamp on threads. Remove jam
nuts and loosen adjustment nuts so there is slack in
the cables.
6. Remove the hardware securing push bar to turnta-
ble and telescope cylinder.
7. Using a suitable brass drift, carefully drive the push
bar pins from the telescope cylinder rod and turnta-
ble.
8. Remove hardware securing cable adjustment block
to aft end of the base boom section and remove
block.
9. Remove hardware securing telescope cylinder to aft
end of the mid boom section.
WHEN REMOVING THE TELESCOPE CYLINDER FROM 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 POSITION: DAMAGE TO COMPO-
NENTS MAY RESULT FROM FORCIBLE IMPACT WITH THESE
ASSEMBLIES.
10. Remove bolts securing cable attach bar to top of fly
boom section.
11. Pull the telescope cylinder and cables partially from
aft end of the base boom section; secure the cylin-
der with a suitable sling and lifting device at approxi-
mately the center of gravity.
12. Carefully remove the telescope cylinder and sheave
assembly. Place telescope cylinder on a suitable
trestle.
Main Boom Telescope Cylinder Installation
1. Route extend cables around extend sheave and
secure cables to the telescope cylinder.
2. Install extend cables mounting blocks to threaded
ends of cables. Loosely install nuts and jam nuts
onto the threaded end of cables.
NOTE: When installing cables care must be taken not to
twist or cross the cables.
3. 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.
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.