SkyTrak 6036 Service Manual - Manual (Page 189)

Section 9 Hydraulic System
Model 6036/6036T S/N 9B0500 thru 14833 9-39
5. Position the hoist cylinder so that the rod is
aligned with the rod end mounting holes as
much as possible.
6. Instruct the operator to raise or lower the hoist
cylinder slowly until the rod end eye is aligned
with the outer boom mounting holes. Secure
the rod end to the boom with pivot pin and its
locking capscrew and locknut.
6. Raise the boom as far as it will go; then lower
it as far as it will go five times or until the
operation of the boom hoist cylinders is normal
(no jerks or spongy feel).
7. Shut down the engine. Check the hydraulic oil
level and fill as described in the Owners/
Operators Manual.
8. Test boom raise/lower circuit operation as
described in paragraph 9.2.2.c.
9.5.3 “BHE” Boom Hoist Cylinder
a. Disassembly
1. Remove all dirt and grease from the cylinder.
2. Fasten the cylinder in a soft-jawed vise or
other acceptable holding equipment. Do not
damage the tube.
3. If necessary to replace, remove the grease
fitting (26, Fig. 9.20) and plugs (3, 4 and 6).
4. Remove the counterbalance valve (7) with O-
rings (8, 10 and 12) and backup rings (9 and
11) from tube (2).
IMPORTANT: Do not attempt to reset the boom
hoist cylinder counterbalance valves. If replace-
ment is necessary, replace both left and right hoist
cylinder cartridges at the same time with new
ones.
5. Using a pin spanner wrench, unscrew the
head (22) from the tube.
IMPORTANT: Protect the finish on the rod at
all times. Damage to the surface of the rod can
cause premature seal failure.
6. Pull the rod (24) and attached parts straight
out of the tube.
IMPORTANT: When sliding the rod and piston
assembly in the tube, be careful so that head
threads in the tube do not damage the piston (13).
Keep the rod in line with the tube barrel to prevent
binding.
7. Remove the bearing (14) and seal and ex-
pander assembly (15) from the piston.
8. Fasten the eye end of the rod (24) in a soft-
jawed vise and put a padded support below
the rod near the piston to prevent damage to
the rod.
NOTE: It may be necessary to apply heat to break
the bond of the sealant between capscrew (1) and
rod (24) before the piston can be removed. Refer
to paragraph 9.5.a.
9. Remove the capscrew (1), piston (13), and
head (22) from the rod.
10. Remove the backup rings (16) and O-ring (17)
from the inside of the piston.
11. Remove the O-ring (18), backup ring (23), O-
ring (21), wiper (19) and rod seal (20) from the
head.
12. If bushing (25) needs replacement, support
the rod (24) in a soft-jawed vise or other
acceptable holding equipment. Carefully
press or drive bushing from the rod eye.
NOTE: It may be necessary to apply heat to break
the bond of the sealant between bushing (25) and
rod (24) before the bushing can be removed.
Refer to paragraph 9.5.a.
b. Cleaning
1. Discard all seals and backup rings. Replace
with a complete new seal kit.
2. Clean all metal parts in an approved cleaning
solvent such as trichlorethylene. Be sure to
carefully clean cavities and grooves.
c. Inspection, Repair and Replacement
1. Check that the rod of the boom hoist cylinder
is straight. If the rod is bent, install new rod.
2. Inspect the inside of the tube for scoring and
other damage. If the tube is damaged,
replace with new tube.
3. Remove small scratches on the rod or inside
the tube with emery cloth of very fine grit.
Use the emery cloth with a rotary motion.
4. Remove staking burrs from the nut and the
bottom of piston with a fine file. Clean parts
with trichlorethylene after repair.
d. Assembly
NOTE: Follow general assembly instructions in
paragraph 9.5.c
1. Apply Loctite ® Primer T and Retaining Com-
pound 609 to the outside diameter of the
bushing (25, Fig. 9.20) in accordance with the
manufacturer’s instructions. Press the