Wiper Seal Installation - JLG 400S Service And Maintenance Manual

2. Use a soft mallet to tap a new wiper seal into the appli-
cable cylinder head groove. Install a new retaining ring
and bearing into the applicable inside diameter of the
cylinder head groove.
Figure 5-75. Wiper Seal Installation
3. Place new o-rings and backup ring in the applicable out-
side diameter groove of the cylinder head.
O-RING
BACKUP RING
Figure 5-76. Installation of Head Seal Kit
4. Carefully install the cylinder head on the rod, ensuring
that the wiper seal, bearing, retaining ring, backup ring
and rod seals are not damaged or dislodged. Push the
head along the rod to the rod end, as applicable.
5. Using suitable protection, clamp the cylinder rod in a
vise or similar holding fixture as close to piston as
possible.
6. Place new o-ring in the applicable inside diameter of the
piston.
7. Carefully thread the piston on the cylinder rod, hand
tight, ensuring that the o-ring and backup rings are not
damaged or dislodged.
8. Install the setscrew and ball on the piston and attach the
piston on the rod.
9. Remove the cylinder rod from the holding fixture.
10. Place new piston seal in the outer piston diameter
groove. (A tube, with I.D. slightly larger than the O.D. of
the piston is recommended to install the solid seal).
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SECTION 5 - BASIC HYDRAULICS INFORMATION & SCHEMATICS
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.
O-RING
12. With barrel clamped secured and adequately support-
MAF00310
13. Continue pushing the rod into the barrel until the cylin-
14. Screw the cylinder head into the barrel using a hook
15. Caulk at the machined area of the cylinder barrel end so
16. After the cylinder has been reassembled, the rod should
17. Install the plugs in the cylinder ports.
PISTON SEAL
Figure 5-77. Installation of Piston Seal Kit
ing the rod, insert the piston end into the barrel cylinder.
Ensure that the piston loading o-ring and piston seal is
not damaged or dislodged.
der head can be inserted into the barrel cylinder.
spanner wrench and torque cylinder head to 549 ft. lbs.
(745 Nm).
that it locks the cylinder head in place and it does not
unscrew from the barrel.
Figure 5-78. Caulking
be pushed all the way in (fully retracted) prior to the
reinstallation of any plugs.
MAF00320
MAF00120
5-79