JLG 510AJ Service Manual - Manual (Page 93)

SECTION 3 - CHASSIS AND TURNTABLE
3121181 – JLG Lift – 3-51
Assembly
1. Install new O-ring (1) and piston seal (2) to the servo pis-
ton (3). Install the piston seal over the O-ring.
Installing the piston seal stretches it, making it difficult
to install the servo piston in its bore. Allow 30 minutes
for the seal to relax after installation. To speed up seal
relaxation, compress the seal by installing the piston
head into the servo cavity in the end-cap and let it stand
for at least five minutes.
2. After piston seal has relaxed, lubricate and install servo
piston into the housing bore. Align the piston with the
ball socket facing the inside of the housing.
RISK OF PERSONAL INJURY: COMPRESSING THE BLOCK SPRING REQUIRES ABOUT
80 TO 90 LBF (350 TO 400 N) OF FORCE. USE A PRESS SUFFICIENT TO MAINTAIN
THIS FORCE WITH REASONABLE EFFORT. ENSURE THE SPRING IS SECURE BEFORE
ATTEMPTING TO INSTALL THE SPIRAL RETAINING RING. RELEASE THE PRESSURE
SLOWLY AFTER THE RETAINING RING IS INSTALLED.
3. Install inner block spring washer (4), block spring (5),
and outer washer (6) into cylinder block. Using a press,
compress the block spring enough to expose the retain-
ing ring groove. Wind the spiral retaining ring (7) into
the groove in the cylinder block.
4. Turn the block over and install the retaining ring (8),
hold-down pins (9), and ball guide (10) to the cylinder
block.
5. Install the pistons (11) to the slipper retainer (12). Install
the piston/retainer assembly into the cylinder block.
Ensure the concave surface of the retainer seats on the
ball guide. If you're reusing the pistons, install them to
the original block bores. Lubricate the pistons, slippers,
retainer, and ball guide before assembly. Set the cylinder
kit aside on a clean surface until needed.
3
2
1
3
1. O-ring
2. Piston Seal
3. Servo Piston
Figure 3-36. Servo Piston
7
6
5
4
8
9
10
12
11
4. Block Spring Washer
5. Block Spring
6. Outer Washer
7. Spiral Retaining Ring
8. Retaining Ring
9. Holddown Pins
10. Ball Guide
11. Piston
12. Slipper Retainer
Figure 3-37. Cylinder Kit Assembly