JLG 680S, Service And Maintenance Manual

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SECTION 5 - BASIC HYDRAULICS INFORMATION & SCHEMATICS
3121234 5-37
14. Rotate the capscrews evenly and progressively in rota-
tion to 9 ft. lbs. (12 Nm).
15. Remove the cylinder rod from the holding fixture.
16. Place new T-seal and wear rings 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).
17. 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.
18. With barrel clamped secured, and adequately support-
ing the rod, insert the piston end into the barrel cylinder.
Ensure that the piston loading T-seal and wear rings are
not damaged or dislodged.
19. Continue pushing the rod into the barrel until the cylin-
der head gland can be inserted into the barrel cylinder.
20. Apply JLG Threadlocker P/N 0100011 to the socket head
capscrews and secure the cylinder head gland using the
washer ring and capscrews. Torque capscrews to
55 ft. lbs. (75 Nm).
21. After the cylinder has been reassembled, the rod should
be pushed all the way in (fully retracted) prior to the re-
installation of any holding valve or valves.
22. Install the valve assembly.
O-RING
BACKUP
RING
WEAR RING
WEAR
RING
T-SEAL
Figure 5-77. Piston Seal Kit Installation
BARREL
PISTON
ROD
HEAD
SPACER
WASHER RING
CAPSCREW
ROD
Figure 5-78. Rod Assembly Installation