4 — MAINTENANCE
4-9
Hydraulic Cylinder Repair
CAUTION
Removing the hydraulic cylinder from the Cougar Lift requires major disassem-
bly of the unit. Contact Bil-Jax before removing the hydraulic cylinder from the
unit for assistance.
Hydraulic Cylinder Removal
It is recommended that Bil-Jax be contacted for assistance before removing the hydraulic
cylinder.
1. Be sure cylinder is completely retracted and pressure is released from the sys-
tem. Place a pan underneath the hydraulic cylinder to catch the hydraulic oil.
2. Disconnect the hydraulic hose from the bottom of the cylinder and drain the hy-
draulic oil. Remove the two bolts, washers, and nuts securing the bottom of the
cylinder to the base.
3. Remove the plexiglass cover from the base.
4. Remove the mounting bolt, washer, and nut securing the top of the hydraulic
cylinder to the lower mast.
5. Disconnect the two lift chains from the base mast.
6. Using a crane with at least one ton of lifting capacity, lift the lower mast section
high enough to remove the clamp securing the cylinder to the base, and remove
the cylinder from the unit.
7. After maintenance has been performed on the hydraulic cylinder, follow the re-
moval procedure in reverse to reinstall the cylinder in the unit.
Hydraulic Cylinder Repair Procedure
Perform the following procedure to repair and maintain the hydraulic lift cylinder. Refer
to Figure 4-6. It is recommended that whenever the hydraulic cylinder is disassembled,
all seals be replaced; order seal repair kit B02-13-0097.
1. Remove gland nut (3, Figure 4-6) with gland nut seal (4), rod wiper (2), and
o-ring (5) from the cylinder jacket (1).
2. Remove piston rod (6) and wear ring (7). Inspect piston rod (6) for any
scratches or pits. Pits that go into the base metal are unacceptable. Scratches that
catch the fingernail, but are not through the base metal or less than 1/2 inch long
and are around the rod are acceptable providing they are not sharp enough to cut
the seal. The rod surface should not have any of the chrome worn through. Re-
place the cylinder if any of these conditions are not met.
3. Clean inside the cylinder jacket (1) and inspect for any scratches or pits. Pits
that are deep enough to catch the fingernail are unacceptable. Scratches that
catch the fingernail, but are less than 1/2 inch long and are around the tube are
acceptable providing they are not sharp enough to cut the seal. Replace the cyl-
inder if any of these conditions are not met.
4. Install wear ring (7) into the grooves at the bottom of the piston rod (6). Lubri-
cate assembly with hydraulic fluid and place back into cylinder jacket (1).
5. Lubricate rod wiper (2), gland nut seal (4), and o-ring (5) with hydraulic fluid.
6. Twist gland nut seal (4) into a “C” shape and insert it with lip side down into the
groove inside the gland nut (3). Place o-ring (5) over the threads of the gland
