JLG 3246E2 Service Manual - Manual (Page 20)

SECTION 2 - PROCEDURES
2-8 – JLG Sizzor – 3120855
1. Using a special tool, pictured in the following illustra-
tion, install a new rod seal into the applicable cylin-
der head gland groove.
WHEN INSTALLING NEW "PARKER" TYPE PISTON SEALS,
ENSURE SEALS ARE INSTALLED PROPERLY. IMPROPER SEAL
INSTALLATION COULD RESULT IN CYLINDER LEAKAGE AND
IMPROPER CYLINDER OPERATION.
2. Using a soft mallet, tap a new wiper seal into the
applicable cylinder head gland groove. Install a new
wear ring into the applicable head gland groove.
3. Place a new o-ring and back-up seal in the applica-
ble outside diameter groove of the cylinder head.
4. Install a washer ring onto the rod, then 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, as
applicable.
5. Carefully slide the piston spacer onto the rod.
6. If applicable, correctly place a new o-ring and back-
up rings in the inner piston diameter groove.
7. Using suitable protection, clamp the cylinder rod in
a vise or similar holding fixture as close to the piston
as possible.
8. Carefully place the piston on the cylinder rod hand
tight, ensuring that the o-ring and back-up rings are
not damaged or dislodged.
9. Place the piston onto the rod until it abuts the spacer
end and install the seal and guidelock ring.
10. Place the locknut on the end of the cylinder rod and
tighten.
11. Remove the cylinder rod from the holding fixture.
12. Thoroughly rinse the inside of the rod weldment and
allow to drain. Wipe with a lint free rag.
13. Clean and visually inspect all parts for material
defects and contamination.
14. Lubricate the head, piston, and all seals with hydrau-
lic fluid prior to installation.
15. When the rod is ready to be installed in the rod weld-
ment, liberally apply an anti-seize lubricant.
16. Cover the entire rod assembly with hydraulic fluid
and with the rod weldment positioned in a suitable
holding fixture insert the rod into the rod weldment.
17. Using a spanner wrench tighten the cylinder head.
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.
18. After the cylinder has been reassembled, the rod
should be pushed all the way in (fully retracted) prior
to the reinstallation of any holding valve or valves.
19. If applicable, install the cartridge-type holding valve
and fittings in the port block using new o-rings as
applicable. For proper holding valve torque specifi-
cations refer to Table 2-2, Holding Valve Torque
Specifications.
Figure 2-5. Rod Seal Installation
Table 2-1. Cylinder Component Torque Specifications.
Component Torque Value (w/Loctite)
Piston Nut - Lift Cylinder - 1932E2 375-450 ft lb
(508-610 Nm)
Piston Nut - Lift Cylinder - 2032E2/
2646E2/3246E2
800-1000 ft lb
(1085-1356 Nm)
Table 2-2. Holding Valve Torque Specifications.
Description Torque Value
1932E2, 2032E2 - Hydraforce -
1.25" hex 3/4 - 16 thds
20 ft lb (27.1 Nm)
2646E2/3246E2 - Hydraforce - 1"
hex 7/8 - 14 thds
25 ft lb (33.9Nm)