Rod seal installation -26, Cylinder head seal installation -26, Piston seal installation -26 – JLG 450A_AJ Series II Service Manual User Manual
Page 266
SECTION 5 - HYDRAULICS
5-26
– JLG Lift –
3121290
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 in cylinder head
gland groove.
Figure 5-47. Rod Seal Installation
IMPROPER SEAL INSTALLATION CAN CAUSE CYLINDER LEAKS AND IMPROPER
CYLINDER OPERATION.
2.
Install wear ring in cylinder head. Install seal and wiper
in cylinder head groove. Install new wear ring in cylinder
head groove. Install new backup ring and O-ring in out-
side diameter groove of cylinder head.
Figure 5-48. Cylinder Head Seal Installation
3.
Slide End Cap on rod with threads facing open end of
rod.
4.
Carefully install assembled head on rod. Make sure
wiper and rod seals are not damaged or dislodged. Push
head along rod to rod end.
5.
Install O-ring inside spacer (450AJ only). Carefully slide
spacer on rod to marked position. Apply locking com-
pound to setscrew (450A only). Tighten setscrew.
6.
Insert new O-ring in rod groove. Install seal on center of
piston. Install wear rings on each end of piston.
Figure 5-49. Piston Seal Installation
7.
Using suitable protection, clamp cylinder rod in a vise or
similar holding fixture as close to piston as possible.
8.
Carefully slide assembled piston on cylinder rod. Make
sure O-ring is not damaged or dislodged.
9.
Apply locking primer and locking compound to rod
threads. Install nut and torque to 200 ft-lb (270 Nm).
Tighten setscrew to 100 in-lb (11 Nm).
10.
Remove cylinder rod from holding fixture.
11.
Position cylinder barrel in a suitable holding fixture.
INSTALLING ROD OFF-CENTER CAN DAMAGE PISTON AND CYLINDER BARREL SURFACES.
USE EXTREME CARE WHEN INSTALLING CYLINDER ROD, HEAD, AND PISTON.
12.
Clamp barrel clamped securely and support rod. Insert
piston end into barrel cylinder. Do not damage or dis-
lodge piston loading O-ring and seal ring.
13.
Continue pushing rod and cylinder head into barrel.
14.
Apply locking compound to barrel threads and tighten
end cap using strap wrench.