SkyTrak 8042 Service Manual User Manual
Page 547
Hydraulic System
8.132
Model 8042, 10042, 10054 Legacy
Rev. 10/03
For S/N 19235 & After
b. Lift/Lower Cylinder Disassembly
Note: An additional o-ring may be included at the base
of the cylinder rod. This additional o-ring may be
discarded, as it served only in a temporarily protective
role.
1. Clean the lift/lower cylinder (1) with a suitable
cleaner. Remove all dirt, debris and grease from the
cylinder.
IMPORTANT: Avoid using excess force when clamping
the cylinder in a vise. Apply only enough force to hold the
cylinder securely. Excessive force can damage the
cylinder tube (2).
2. Secure the lift/lower cylinder in a soft-jawed vise or
other acceptable holding equipment if possible.
3. Slowly remove the counterbalance valve (3) and pilot-
operated check valve (4) from the tube (2).
IMPORTANT: DO NOT tamper with or attempt to reset
the counterbalance valve cartridge. If adjustment or
replacement is necessary, replace the counterbalance
valve with a new part.
4. Extend the rod (5) as required to allow access to the
base of the cylinder.
IMPORTANT: Protect the finish on the rod at all times.
Damage to the surface of the rod can cause seal failure.
5. Using a pin spanner wrench, unscrew the locking collar
(6) from the tube (2). The locking collar was
originally torqued to 300-400 lb-ft (407-542 Nm), so
a considerable amount of force is required.
6. Carefully slide the locking collar (6) and the head
gland (7) down along the rod toward the eyelet end,
away from the cylinder tube (2).
IMPORTANT: When sliding the rod and piston assembly
out of the tube, prevent the threaded end of the tube
from damaging the piston (8). Keep the rod centered
within the tube to help prevent binding.
7. Carefully pull the rod (5) with all attachments straight
out of the tube (2).
8. Fasten 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.
MH4300
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