Lull 6K Service Manual - Manual (Page 498)

Note: Older production models do not have a stroke limiter. This includes
S/N 101–433 for 644B-37, S/N 101–130 for 644B-42, S/N 101–323 and
326–328 for 844C-42, S/N 101–109 for 1044C-42, and S/N 101–108 for
1044C-54.
7. Remove all O-rings, wear rings, and backup rings from cylinder
components and discard.
8. Thoroughly clean components with solvent and dry with compressed
air. Inspect and replace if damaged.
9. Inspect inner surface of barrel, outer surface of piston, and length of
rod for scratches and scoring. If barrel, piston, or rod is damaged, it
must be replaced.
10. Check condition of threads on rod, nut, and capscrews. Do not attempt
to repair damaged threads.
11. Lubricate new O-ring with hydraulic oil and install inside piston (seals
rod to piston).
12. Lubricate new O-ring, backup ring, seals, and wear rings with hydraulic
oil and install on head. Using a seal driver, install new wiper seal in
head. Lubricate wiper seal with hydraulic oil.
13. Slide rod bearing head (Item 8), stroke limiter (Item 6), and piston
(Item 5) onto rod (Item 7). Lubricate threads on rod with hydraulic oil
and install rod nut (Item 4). For older production models with a 1" rod
nut, torque rod nut to 740 ft-lbs. For more recent production models
with a 1-1/4" rod nut, torque rod nut to 930 ft-lbs.
14. Lubricate new seal and wear rings with hydraulic oil and install on
piston.
15. Install spanner wrench on rod bearing head using the three (3) holes in
side the head. Tighten rod bearing head until it is snug against the
cylinder barrel.
16. Install connector to cylinder barrel and torque to 46–50 ft-lbs.
17. Install dowel pin (Item 1) in end of cylinder barrel.
6-248 Service Manual — Models 644B, 6K, 844C, 8K, 1044C, 10K