HYDRAULIC SYSTEM RT880E SERVICE MANUAL
2-100 Published 11-10-2014, Control # 524-00
COUNTERWEIGHT REMOVAL CYLINDER
Description
The counterweight removal cylinder, Figure 2-54, has a 3.50
in (8.89 cm) diameter bore. The retracted length of the
cylinder is 9.25 in (23.4 cm) from the center of the rod
bushing to the center of the barrel bushing. The extended
length of the cylinder is 34.25 in (86.9 cm). The stroke of the
cylinder is 25 in (63.5 cm). A wiper ring prevents foreign
material from entering each cylinder. O-rings and other seals
prevent internal and external leakage.
The cylinder weighs approximately 93.9 lb (42.63 kg).
Maintenance
Disassembly
NOTE: Any maintenance requiring disassembly of the cyl-
inders should include replacement of all seals and
rings. A seal kit will supply the required items.
1. Remove the counterbalance valves from the port block.
2. Clean away all dirt from the head and ports. Place pro-
tective padding around the rod near the head to prevent
damaging the chrome during head removal.
3. Secure the cylinder with ports facing down using clamps
or a vise to prevent rolling.
4. Using a means of collecting the oil, carefully remove the
plugs. Since high pressure may be trapped in the cylin-
der, remove the port plugs and counterbalance valves
and allow cylinder to drain
5. With the cylinder secured, pull the rod to full extension to
remove additional oil. Keeping the rod supported, tap
the rod back in 1 in (2.54 cm) after all oil has drained.
6. Using a spanner wrench, unscrew the head from the
barrel. After unthreading, tap the head out with a rubber
mallet and allow any excess fluid to drain into catch pan.
7. With the rod still supported, gently pull the piston from
the tube assembly being careful not to cock the piston in
the tube. Place the rod assembly on a surface that will
not damage the chrome or allow the rod assembly to
drop.
NOTE: Cover the barrel opening to avoid contamination.
8. Remove the wear ring from the outside of the piston to
gain access to the setscrew.
NOTE: Arranging discarded seals and rings in the order of
disassembly will aid in installation of new seals and
rings. Pay attention to how each seal and ring is
installed to avoid installing replacement seals and
rings improperly.
9. Loosen the piston’s setscrew. Remove the piston from
the rod.
10. Remove the spacer from the rod.
11. Remove the other wear ring and seal from the outside of
the piston.
12. Remove the head from the rod.
13. Remove the O-ring and backup ring from the outside of
the head. Remove the rod seal, wiper and O-ring from
the inside of the head.
Inspection
1. Inspect the rod. There should be no scratches or pits
deep enough to catch the fingernail. Pits that go to the
base metal are unacceptable. Chrome should be pres-
ent over the entire surface of the rod. If lack of chrome
on rod, the rod should be replaced.
2. Inspect rod for straightness. Determine if it can be
straightened or must be replaced.
3. Inspect the head. Visually inspect the inside bore for
scratching or polishing. Deep scratches are unaccept-
able. Polishing indicates uneven loading, and the bore
should be checked for out-of-roundness.
4. Inspect the piston. Visually inspect the outside surface
for scratches or polishing, Deep scratches are unaccept-
able. Polishing indicates uneven loading, and the diame-
ter should be checked for out-of roundness.
5. Inspect the barrel carefully for scoring. If barrel is
scored, it must be repaired or replaced.
6. Thoroughly rinse parts, allow to drain, and wipe with a
lint-free rag. Inspect all parts for serviceability.
WARNING
Do not use air pressure to remove the rod. Use only a
source of controlled hydraulic oil pressure if the rod is
hard to move.
CAUTION
Exercise extreme care when handling or setting down the
rod. Damage to the rod surface may cause unnecessary
maintenance and expense.
CAUTION
When removing seals and rings, avoid scratching the
grooved and gland surfaces.
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