JLG 4013PS Service Manual - Manual (Page 138)

Hydraulic System
8-28 3508PS, 3509PS, 3512PS, 3513PS, 4008PS, 4009PS, 4012PS, 4013PS, 4017PS, 40.8, 40.9
4. Lubricate and slide the head gland (6) over the
cylinder rod (5). Install the piston head (4) on to the
end of the cylinder rod. Apply Loctite
® 243 TM to the
setscrew (3) and install in the piston head. Refer to
Section 8.10.9, “Hydraulic Cylinder Torque
Specifications,” for tightening guidelines for the
piston head and the set screw.
Note: Avoid using excessive force when clamping the
cylinder barrel in a vise. Apply only enough force to hold
the cylinder barrel securely. Excessive force can
damage the cylinder barrel.
5. Place the cylinder barrel (1) in a soft-jawed vise or
other acceptable holding equipment if possible.
Note: When sliding the rod and piston assembly into the
cylinder barrel, prevent the threaded end of the cylinder
barrel from damaging the piston head. Keep the cylinder
rod centered within the barrel to prevent binding.
6. Carefully insert the cylinder rod assembly into the
tube.
7. Screw the head gland (6) into the cylinder barrel (1)
and tighten with a spanner wrench. Refer to Section
8.10.9, “Hydraulic Cylinder Torque Specifications,”
for tightening guidelines for the head gland.
8. If applicable, thread the new counterbalance valve
into the block on the cylinder barrel.
8.10.6 General Cylinder Installation
1. Grease the bushings at the ends of the hydraulic
cylinder. Using an appropriate sling, lift the cylinder
into it’s mounting position.
2. Align cylinder bushing and install pin, lock bolt or
retaining clip.
3. Connect the hydraulic hoses in relation to the labels
or markings made during removal.
4. Properly connect the battery.
5. Before starting the machine, check oil level of the
hydraulic oil reservoir and if necessary, fill to full
mark with hydraulic oil.
6. Start the machine and run at low idle for about one
minute. Slowly activate hydraulic cylinder function in
both directions allowing cylinder to fill with hydraulic
oil.
7. Inspect for leaks and check level of hydraulic oil in
reservoir. Add hydraulic oil if needed. Shut the
engine OFF.
8. Wipe up any hydraulic oil spillage in, on, near and
around the machine, work area and tools.
9. Remove the Do Not Operate Tags from both the
ignition key switch and the steering wheel.
8.10.7 Cylinder Pressure Checking
Attach a 345 bar (5000 psi) gauge to the test port on the
main control valve to check the system pressure.
Note: If a hydraulic cylinder pressure is greater than the
main control valve pressure, increase the main control
valve pressure by adjusting the main relief. Generally,
one half turn clockwise will be adequate to check an
individual circuit. Activate the circuit and if pressure is
obtained, turn the main relief counter clockwise one half
turn. Recheck the main relief setting and adjust if
necessary.
8.10.8 Steering Cylinders
The steering cylinders (7) are attached to each axle
center housing. The steer cylinders are covered in the
appropriate manufacturer’s axle literature.
7
AXLE CENTER SECTION