JLG 4394RT - Swash Plate & Servo Piston

SECTION 3 - CHASSIS, PLATFORM & SCISSOR ARMS
3121642 – JLG Lift – 3-27
23. Turn housing over and remove the swashplate (39) by
lifting on the end opposite the servo lever.
24. Remove the servo piston (40). Remove the piston seal
(41) and O-ring (42) from the servo piston. Discard the
seal and O-ring.
25. Remove the journal bearings (43) from the housing. If
the bearings are to be reused, note the location and ori-
entation of each bearing for reassembly.
26. Remove pistons (44) and slipper retainer (45) from the
cylinder block (46).
The pistons are not selectively fitted, however units with
high hourly usage may develop wear patterns. Number
the pistons and bores for reassembly if they are to be
reused.
27. Remove the ball guide (47), hold-down pins (48), and
retaining ring (49) from the cylinder block.
NOTE: Most repairs do not require block spring removal. Perform
this procedure only if you suspect problems with the block
spring.
RISK OF PERSONAL INJURY: COMPRESSING THE BLOCK SPRING REQUIRES
FORCE OF ABOUT 80 TO 90 LBF (350 TO 400 N). USE A PRESS SUFFICIENT TO
MAINTAIN THIS FORCE WITH REASONABLE EFFORT. ENSURE THE SPRING IS
SECURE BEFORE ATTEMPTING TO REMOVE THE SPIRAL RETAINING RING.
RELEASE THE PRESSURE SLOWLY AFTER THE RETAINING RING IS REMOVED.
41
42
40
Lift here
39
43
39. Swashplate
40. Servo Piston
41. Piston Seal
42. O-ring
43. Journal Bearings
Figure 3-15. Swash Plate & Servo Piston
51
50
52
53
46
49
48
47
45
44
44. Piston
45. Slipper Retainer
46. Cylinder Block
47. Ball Guide
48. Holddown Pins
49. Retaining Ring
50. Block Spring Washer
51. Spiral Retaining Ring
52. Block Spring
53. Inner Block Spring Washer
Figure 3-16. Cylinder Kit Disassembly