JLG sky trak mmv Service Manual page 478

Hydraulic System
18. Test the cylinder at low operating pressure
(100 psi or 6,9 bar) to verify that the piston and rod
move freely in both directions.
19. Increase the operating pressure to the maximum for
the cylinder (4500 psi or 310 bar) and check for
external leakage and for free movement in both
directions.
20. Retract the piston fully.
f. Fork Side Shift Cylinder Installation
1. Assemble the new pawl pads (1) into the cavities of
the rod end pawl (2). Spray each pad with 3M #90
High Strength Spray and insert into each cavity.
2
2. Clamp the rod end pawl in a vise.
3. Apply Loctite Threadlocker 277 (red) High Strength
to the threads of the cylinder rod (3). Line up the rod
end pawl (4) with the cylinder rod (3). Turn the rod
until the rod end pawl bottoms on the threads of the
cylinder rod. Use a large flat blade screwdriver to
turn the cylinder rod inside the rod end pawl. Insert
the screwdriver in through the opening in the rod end
pawl and into the slot (5) in the end of the cylinder
rod.
9.180
1
MM3900
5
4
3
MM3970
4. Place the base end of the cylinder in place behind
the retaining plate on the outer edge of the carriage.
Turn the rod end pawl till the wear pads sit squarely
against the surfaces of the carriage.
5. Position the cylinder (6) in place and reassemble the
cylinder retainer plates (7), retainer plate shims (8)
and the cylinder retainer spacer cams (9). Insert the
capscrews (10) through the cams, plates, shims and
mounting plate (11) on the carriage. Secure in place
with the hex nut (12). Turn the spacer cams to
securely hold the cylinder in place and tighten both
hex nuts securely.
11
12
8
7
9
6
10
MM3941
Model MMV Rev. 12/04