Lull 6K Service Manual - Manual (Page 462)

Boom and Transfer
6-212 Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K
1. Remove base mount from the cylinder barrel as follows:
For Models 1044C-54 (S/N 101–143) and 10K-54 (S/N 101–103)
Remove three (3) each capscrews (Item 1) and flatwashers (Item 2)
along with the extension cylinder base mount (Item 3) from the cylinder
barrel (Item 8).
For Models 1044C-54 (S/N 144–) and 10K-54 (S/N 104–):
Remove two (2) each capscrews (Item 1) and flatwashers (Item 2)
along with the extension cylinder base mount (Item 3) from the cylinder
barrel (Item 8).
2. Mount or support cylinder vertically with rod end down. Hydraulic oil in
cylinder will drain out during disassembly. Place a suitable pan or tray
under the cylinder.
3. Release pressure in counterbalance valve cartridges (Items 5 and 6)
as follows:
WARNING: Counterbalance valve cartridges trap hydraulic pressure in the
cylinder. Wear proper eye and hand protection when removing
counterbalance valve cartridges. Hydraulic fluid under
pressure can be injected under skin or into eyes, resulting in
serious personal injury or death.
a. Place socket wrench over counterbalance valve cartridge. Wrap a
clean shop rag around the socket to cover the area of the
counterbalance valve cartridge.
b. Carefully and slowly, turn cartridge out of manifold block to release
pressure in cylinder.
4. Remove the counterbalance valve cartridges.
5. Slowly extend and retract cylinder by hand to remove most of the
hydraulic oil.
6. Remove eight (8) capscrews (Item 12) securing rod bearing head
(Item 11) to cylinder barrel.
7. Remove cylinder rod (Item 13) from cylinder barrel.
CAUTION: To prevent possible damage to components, support rod and
head; do not wiggle rod or head back and forth during
removal.
8. Remove rod nut (Item 9), piston (Item 10), and rod bearing head from
cylinder rod.
9. Remove the two (2) elbows (Item 7) from cylinder barrel.
10. Remove four (4) O-ring plugs (Item 4) from cylinder manifold block.
11. Remove all O-rings, wear rings, and backup rings from cylinder
components and discard.
12. Thoroughly clean components with solvent and dry with compressed
air. Inspect and replace if damaged.