JLG 660SJ Service Manual - Manual (Page 193)

SECTION 4 - BOOM & PLATFORM
3121202 – JLG Lift – 4-21
6. Place two (2) 3/8"x16NC bolts in threaded holes in
bottom of the actuator. Using a suitable bar, unscrew
the end cap (5). Remove the end cap from actuator
(1).
7. Remove the shaft (2) from piston sleeve (3) and the
actuator housing (1).
8. Remove piston sleeve (3) from housing (1).
9. Remove all seals and bearings from grooves. Dis-
card seals.
Inspection
1. Clean all parts thoroughly.
2. Closely inspect all parts for excessive wear, cracks
and chips. Replace parts as necessary.
NOTE: A small amount of wear in the spline teeth will have
little effect on the actuator strength. New spline sets
are manufactured with a backlash of about 0.005 in.
per mating set. After long service, a backlash of
about 0.015 per set may still be acceptable in most
cases, depending on the required accuracy of the
application.
3. Check the ring gear for wear and weld damage to
the pins.
4. Inspect the cylinder bore for wear and scratches.
Assembly
NOTE: Lubricate all seals and o-rings with clean hydraulic
oil prior to assembly.
1. Install new seal (7) and bearing (6) on the piston
sleeve (3).
NOTE: Apply a coat of grease to the thrust ring before slid-
ing onto the shaft.
2. Install new seal (8), thrust ring (10) and bearing (9)
on shaft (2).
NOTE: Apply a coat of grease to the thrust ring before slid-
ing onto the end cap.
Figure 4-26. Removing End Cap
Figure 4-27. Removing Shaft from Housing
Figure 4-28. Removing Sleeve from Housing