JLG 67SL Service Manual - Manual (Page 82)

SECTION 4 - HYDRAULICS
4-6 – JLG Lift – 3121322
11. Inspect seal and o-ring grooves in head for burrs
and sharp edges. Dress applicable surfaces as nec-
essary.
12. Inspect cylinder head outside diameter for scoring
or other damage and ovality and tapering. Replace
as necessary.
13. If applicable, inspect rod and barrel bushings for
signs of excessive wear or damage. Replace as nec-
essary.
a. Thoroughly clean bushing housing of burrs, dirt,
etc. to facilitate bearing installation.
b. Inspect bushing housing for wear or other dam-
age. If the bushing housing is worn or damaged,
rod/barrel must be replaced.
c. Lubricate inside of bushing housing with WD40
prior to bushing installation.
d. Using an arbor of the correct size, carefully
press the bushing(s) into bushing housing on
the cylinder rod and cylinder barrel, if applica-
ble.
NOTE: Step 14 applies only to the Lift Cylinder.
14. Inspect the hydraulic block, load retaining valve
block, and check valve block for any damage.
Replace as necessary.
15. Inspect the oil ports for blockage or the presence of
dirt or other foreign material. Repair as necessary.
16. If applicable, inspect piston rings for cracks or other
damage. Replace as necessary.
Assembly
NOTE: Prior to cylinder assembly, ensure that the proper
cylinder seal kit is used. See your JLG Parts Manual
3121323. Always replace seals when servicing cylin-
ders.
Apply a light film of hydraulic oil to all components prior to
assembly.
1. A special tool is used to install a new rod seal into
the applicable cylinder head gland groove.
NOTICE
WHEN INSTALLING PISTON SEALS, ENSURE SEALS ARE
INSTALLED PROPERLY. IMPROPER SEAL INSTALLATION COULD
RESULT IN CYLINDER LEAKAGE AND IMPROPER CYLINDER
OPERATION.
WHEN INSTALLING THE WIPER SEAL, APPLY LOCTITE #609 ON
THE WIPER SEAL IN THREE EVENLY SPACED PLACES TO AID IN
RETENTION OF THE SEAL.
2. Use a soft mallet to tap a new wiper seal into the
applicable cylinder head gland groove. Install a new
rod seal into the applicable cylinder head gland-
groove.
Bushing
Arbor
Tool
Bushing
Housing
Figure 4-12. Bushing Installation
ROD
SEAL
Figure 4-13. Rod Seal Installation