SkyTrak 3606 Service Manual - Manual (Page 309)

Hydraulic System
9-115
7. Using a pin spanner wrench, unscrew the gland (5)
from the cylinder tube (2).
IMPORTANT: Protect the finish on the rod at all times.
Damage to the surface of the rod can cause seal failure.
8. Carefully pull the rod (6) with all attachments straight
out of the tube (2).
IMPORTANT: When sliding the rod and piston assembly
in the tube, prevent the threaded end of the tube from
damaging the piston (4). Keep the rod centered within the
tube to help prevent binding.
9. Fasten the eye of the rod (6) in a soft-jawed vise and
put a padded support below and near the threaded
end of the rod to help prevent damage to the rod.
10. Remove the piston nut (7), piston (4) and gland (5)
from the rod (6).
Note: Loctite Threadlocker #271 (red) and 350 lb/ft
(474,6 Nm) of torque were applied to the piston nut when
it was installed. It may be necessary to apply heat to
break the bond of the sealant between the piston nut (7)
and the rod (6) before the parts can be removed. Some
parts of cylinders are sealed with a special organic seal-
ant and locking compound. Before attempting to disas-
semble these parts, remove any accessible seals from
the area of the bonded joint. Wipe off any hydraulic oil
and heat the joint uniformly to break the bond. A temper-
ature of 300° to 400° F (149° to 204° C) will destroy the
bond. Avoid overheating or the parts may become dis-
torted or damaged. Apply sufficient torque or pressure for
removal while the parts are still hot. Breakdown of seal-
ant will leave a white, powdery residue on threads and
parts. Clean the residue away with a soft brass wire
brush prior to reassembly, and wipe with Loctite “T”
cleaner before reinstallation.
11. Remove the piston seal (14) from the piston (4).
12. Remove the small O-ring (13) from inside the piston
(4).
13. Remove the O-ring (11), backup ring (12), wiper (10)
and rod seal (9) from the gland (5).
c. Side Tilt Carriage Cylinder Cleaning
1. Remove all hydraulic fluid, dirt and debris from the
inner surface of the cylinder tube (2, Fig. 9– 75).
2. Discard all seals, backup rings and O-rings. Replace
with new items from a complete seal kit to help
ensure proper cylinder function.
3. Clean all metal parts with an approved cleaning
solvent such as trichlorethylene. Carefully clean
cavities, grooves, threads, etc.If a white, powdery
residue is present on threads and parts, it can be
removed.
4. Clean the residue away with a soft brass wire brush
prior to reassembly, and wipe with Loctite T cleaner
before reinstallation.
d. Side Tilt Carriage Cylinder Inspection
1. Inspect internal surfaces and all parts for wear,
damage, etc. If inner surface of the tube (2,
Fig. 9– 75) does not display a smooth finish, or is
scored or damaged in any way, replace the tube.
Most often, dirty hydraulic fluid causes failure of
internal seals and damage to the smooth surface
within the tube. Remove slight scratches on the
piston, rod, or inner surface of the tube with very fine
grit emery cloth. Use the emery cloth in a rotary
motion to polish out and blend the scratch(es) into
the surrounding surface.
2. Clean parts with trichlorethylene.
3. Check that the rod (6) is straight. If it is bent, install a
new rod.
e. Side Tilt Carriage Cylinder Assembly
Note: Follow the general assembly instructions in Sec-
tion 9.12 c. General Cylinder Assembly.
1. If necessary, press the self-align bearing (8,
Fig. 9– 75) into the cylinder tube eyelet. The bearing
should protrude equally from each side of the eyelet.
2. Install the rod seal (9), wiper (10), backup ring (12)
and O-ring (11) into the gland (5). Orient the parts as
indicated in Fig. 9– 75.
Note: The wiper lip should be toward the inner end of
the gland and the rod seal toward the outer end of the
gland. Use tools that will not damage the seal. If the
backup ring is not flat on both sides, the side with the arc
must be toward the O-ring.
3. Fasten the eye of the rod in a soft-jawed vise and put
a padded support below and near the threaded end
of the rod to help prevent damage to the rod.
4. Push the gland (5) onto the rod (6). If necessary, use
a soft hammer to drive the gland onto the rod.
5. Install a new small O-ring (13) inside the rod end of
the piston (4).
6. Install a new piston seal (14) on the piston (4).
7. Apply Loctite Primer “T” and Threadlocker #271 (red)
to the threads of the piston nut (7) in accordance with
Loctite instructions. Thread the piston nut onto the
rod (6) and torque to 350 lb/ft (474,6 Nm).
8. Fasten the cylinder tube (2) in a soft-jawed vise or
other acceptable holding equipment. DO NOT
damage the tube (2).
9. Lubricate the piston (4), gland (5) and the inside of the tube (2) with clean, filtered hydraulic oil.
Model 3606 • Origin 10/99