JLG 450A_AJ Series II Service Manual - Manual (Page 275)

SECTION 5 - HYDRAULICS
3121290 – JLG Lift – 5-35
ASSEMBLY
NOTE: Use proper cylinder seal kit for cylinder assembly. See your
JLG Parts Manual.
Apply a light film of hydraulic oil to all components before
assembly.
1. Use seal tool to install new rod seal into applicable cylin-
der head gland groove.
Figure 5-66. Rod Seal Installation
IMPROPER SEAL INSTALLATION CAN CAUSE CYLINDER LEAKS AND IMPROPER
CYLINDER OPERATION. ENSURE ‘POLY-PAK’ PISTON SEALS ARE PROPERLY
INSTALLED. REFER TO WIPER SEAL INSTALLATION FOR CORRECT SEAL ORIEN-
TATION.
2. Use a soft mallet to tap new wiper seal into applicable
cylinder head gland groove. Install new wear ring into
applicable cylinder head gland groove.
Figure 5-67. Poly-Pak Piston Seal Installation
Figure 5-68. Wiper Seal Installation
3. Place new O-ring and back-up seal in applicable outside
diameter groove of cylinder head.
Figure 5-69. Installation of Head Seal Kit
4. Install washer ring on rod. Carefully install head gland
on rod. Do not damage or dislodge wiper and rod seals.
Push head along rod to rod end, as applicable.
5. Carefully slide piston spacer on rod.
6. Place new O-ring and back-up rings in inner piston
diameter groove.
Figure 5-70. Piston Seal Kit Installation