SkyTrak 6036 Service Manual - Manual (Page 196)

Section 9 Hydraulic System
9-46 Model 6036/6036T S/N 9B0500 thru 14833
11. If necessary remove the plugs (18) and O-
rings (17) from the tube (16).
9. If removed, install two O-rings (17) and two
plugs (18) in the bottom of the cylinder tube.
10. Lubricate inside of the tube and outside of the
piston and head with clean hydraulic oil.
11. Apply a compression sleeve or other suitable
tool to the head and piston in order to com-
press O-rings, backup rings and seals while
inserting the assembled piston, rod and head
into the tube (16). Remove the compression
tool. Using a pin spanner wrench, thread the
head into 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 seal.
Keep the rod in line with the tube barrel to prevent
binding.
12. Install new O-rings and backup rings (22) on
the counterbalance valve (19) and pilot check
valve (20). Use new valves if either or both
valves were removed for replacement. Lubri-
cate outside of the valves with clean filtered
hydraulic oil. Install the valves and torque
them to 45 lb-ft (61,2 Nm).
13. Following reassembly, test the cylinder at low
operating pressure (100 psi or 6,9 bar) to be
sure the piston and rod are moving freely in
both directions.
14. Increase the operating pressure to the maxi-
mum (4000 psi or 275 bar) for the cylinder and
check for external leakage and free movement
in both directions.
17. Prepare the cylinder for installation by retract-
ing the piston and capping and plugging the
ports.
b. Installation
1. Using suitable lifting device, install the boom
extend cylinder, Fig. 9.21, on the forklift
securing the base end of the extend cylinder to
the outer boom with a pin and retaining rings
and the rod end through the anti-buckle bar.
2. Remove all plugs or caps from the hydraulic
lines and securely tighten the lines to the
cylinder.
a. Assembly
NOTE: Follow general assembly instructions in
paragraph 9.5.c.
1. Install a new O-ring (7), backup ring (6), wiper
(2), rod seal (3), and O-ring (4) on the head as
shown in Fig. 9.23.
NOTE: Lip of wiper (2) should be toward outer
end of head and rod seal (3) toward the inner end
of the head. Use tools that will not damage the
seals. If the backup ring (6) is not flat on both
sides, the side with the arc must be toward o-ring
(7).
2. Fasten the rod eye in a soft-jawed vise. Place
a padded support below and near end of rod
to prevent damage to rod (1).
3. Slide the assembled head and seals onto the
rod. If necessary, use a soft hammer to drive
the head on the rod.
4. Install the snap ring (9) inside of the spacer (8)
and slide the spacer onto rod.
5. Install new backup rings (10) and o-ring (11)
inside internal groove on inside of piston (12).
6. Apply Loctite ® Threadlocker 242 to capscrew
(15) and screw capscrew into the rod and
torque to 950 lb-ft (1288,2 Nm).
7. Install a new seal/expander assembly (13) and
bearing (14) on piston.
8. Fasten cylinder tube (16) in a soft-jawed vise
or other acceptable holding equipment.
c. 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 all cavities and grooves.
d. Inspection, Repair and Replacement
1. Check that the rod is straight. If the rod is
bent, install new rod.
2. Inspect inside of the tube for deep 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.