Oshkosh JLG 1500SJ, Service And Maintenance Manual

Page: 446 / 706

SECTION 5 - BASIC HYDRAULIC INFORMATION & HYDRAULIC SCHEMATICS
5-92 – JLG Lift – 3121262
COULD RESULT IN CYLINDER LEAKAGE AND IMPROPER
CYLINDER OPERATION.
2. Use a soft mallet to tap a new wiper seal into the cylin-
der head gland groove. Install new wear rings into the
cylinder head gland groove.
3. Place a new O-ring and backup ring in the outside diam-
eter groove of the cylinder head.
4. Place the cylinder cap over the rod and carefully install
the head gland on the rod, ensuring that the wiper and
rod seals are not damaged or dislodged. Push the head
along the rod to the rod end.
5. Place a new O-ring and backup rings in the inner piston
diameter groove.
6. Using suitable protection, clamp the cylinder rod in a
vise or similar holding fixture as close to the piston
threads as possible.
7. Install the piston on the cylinder rod hand tight, ensur-
ing that the o-ring and back-up rings are not damaged
or dislodged.
8. Carefully thread the lock nut onto the rod to secure the
piston in place. Torque to 400 ft.lbs. (542 Nm).
9. Remove the cylinder rod from the holding fixture.
10. Place a new wear ring and t-seal in the outer piston
diameter grooves. (A tube, with I.D. slightly larger than
the O.D.of the piston is recommended to install the seal.)
11. Position the cylinder barrel in a suitable holding fixture.
EXTREME CARE SHOULD BE TAKEN WHEN INSTALLING THE
CYLINDER ROD, HEAD, AND PISTON. AVOID PULLING THE
ROD OFF-CENTER, WHICH COULD CAUSE DAMAGE TO THE
PISTON AND CYLINDER BARREL SURFACES.
12. With barrel clamped securely, and while adequately sup-
porting the rod, insert the piston end into the barrel cyl-
inder. Ensure that the piston seals are not damaged or
dislodged.
13. Continue pushing the rod into the barrel until the cylin-
der head gland can be inserted into the barrel cylinder.
14. Secure the cylinder head using JLG Threadlocker (P/N
0100035 and the cylinder cap.
15. After the cylinder has been reassembled, the rod should
be pushed all the way in (fully retracted).
Figure 5-112. Cylinder Head Seal Installation
Figure 5-113. Piston Seal Installation