JLG 534D-10 - Manual (Page 147)

8.23 534D-9, 534D-10 & 544D
Hydraulic System
4. Lubricate and slide the head gland over the cylinder
rod. Install the piston head on to the end of the
cylinder rod. Loctite and install the set screw in the
piston head. Refer to Section 8.9.6, “Cylinder Torque
Specifications,” for torque specifications for the
piston head and the set screw.
5. Place the cylinder barrel in a soft-jawed vise or other
acceptable holding devise.
6. Carefully insert the cylinder rod assembly into the
cylinder barrel.Screw the head gland into the
cylinder barrel and tighten with a spanner wrench.
Refer to Section 8.9.6, “Cylinder Torque
Specifications,” for torque specifications for the head
gland.
7. If applicable, install new counter balance valve into
block on the cylinder barrel.
8.9.4 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. Before starting the machine, check fluid level of the
hydraulic fluid reservoir and if necessary fill to full
mark with Mobilfluid 424
® (ISO 46).
5. 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.
6. Inspect for leaks and check level of hydraulic fluid in
reservoir. Add hydraulic fluid if needed. Shut the
engine OFF.
7. Wipe up any hydraulic fluid spillage in, on, near and
around the machine, work area and tools.
8. Close and secure the engine cover.
8.9.5 Cylinder Pressure Checking
Install a digital or a 10,000 (689 bar) psi gauge to the test
port located at the left side in front of the return filter.Make
sure the gauge can be observed from the operator’s cab.
Refer to Section 8.4.1, “Hydraulic Pressures,” for a
specific hydraulic cylinder circuit pressure setting.
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. Re-check the main relief setting and adjust if
necessary.
NOTICE
Avoid using excess 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.
NOTICE
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.