JLG 600A_AJ Service Manual - Manual (Page 220)

SECTION 5 - HYDRAULICS
5-10 – JLG Lift – 3121201
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, FORK-LIFT, OR OTHER
MEANS TO SUPPORT THE OVERHANGING WEIGHT OF THE
EXTENDING ROD.
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. Extend telescope
up to gain to pin #1.
2. Shut down engine. Support main boom basket end
with a prop (See Figure 5-17., Boom Positioning and
Support, Cylinder Repair.
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 suitable container to retain any residual
hydraulic fluid. Cap hydraulic lines and ports.
4. Remove the retaining rings that retain the telescope
cylinder rod to the fly boom.
5. Using a suitable brass drift, carefully drive telescope
cylinder rod pin #1 from the fly boom.
6. Remove mounting hardware securing the telescope
cylinder barrel end to the base boom.
7. Attach a suitable sling to the telescope cylinder.
Using a suitable lifting device attached to the sling,
carefully pull the cylinder partially from the aft end
boom assembly.
8. Secure the cylinder with a suitable sling and lifting
device at the approximate center of gravity.
9. Carefully lift the cylinder clear of the boom assembly
and lower to the ground or suitably supported work
area.
Main Boom Telescope Cylinder Installation
1. Attach a hydraulic power supply to the telescope
cylinder ports. Using suitable supports or lifting
devices at each end of the cylinder, extend the rod
so that the cylinder pin attach holes are the same
distance apart as the boom pin attach holes.
2. Using suitable lifting equipment, carefully lower the
cylinder to the boom assembly.
3. Install the cylinder into the boom assembly.
4. Remove the lifting devices from the telescope cylin-
der.
5. Carefully install telescope cylinder rod pin #1
through the fly boom and secure it with the retaining
rings.
Table 5-2. Cylinder Head and Tapered Bushing Torque
Specifications
Description
Head Torque
Value (Wet)
Tapered Bushing
Torque Value
(Wet)
Upper Lift
Cylinder 80 ft. lbs.
(109 Nm)
9 ft. lbs.
(12 Nm)
Lower Lift
Cylinder 420 ft. lbs.
(570 Nm)
30 ft. lbs.
(41 Nm)
Articulating Lift
Cylinder 30 ft. lbs.
(41 Nm)
5 ft. lbs.
(9 Nm)
Articulating Slave
Cylinder 50 ft. lbs.
(68 Nm)
9 ft. lbs.
(12 Nm)
Articulating
Master Cylinder 50 ft. lbs.
(68 Nm)
9 ft. lbs.
(12 Nm)
Master Cylinder 30 ft. lbs.
(41 Nm)
5 ft. lbs.
(9 Nm)
Upper Telescope
Cylinder 30 ft. lbs.
(41 Nm)
9 ft. lbs.
(12 Nm)
Tower Telescope
Cylinder 30 ft. lbs.
(41 Nm)
9 ft. lbs.
(12 Nm)
Upright Level
Cylinder 190 ft. lbs.
(260 Nm)
30 ft. lbs.
(41 Nm)
Lockout Cylinder 80 ft. lbs.
(109 Nm)
N/A
Slave Cylinder 30 ft. lbs.
(41 Nm)
9 ft. lbs.
(12 Nm)
Steer Cylinder Piston Nut Torque Specifications
Steer Cylinder LBS. Nm
150 ft. lbs 204 Nm