Hitachi ZAXIS 250LC-7 Operator's Manual page 53

Removing Hoses between the Boom And Arm
IMPORTANT: Bleed air from the hydraulic oil tank before
starting work.
1. Release remaining pressure from the piping before
removing hoses. Refer to the "Operator's Manual for
Hitachi Excavator" for releasing pressure.
2. Disconnect hoses between the boom and arm.
3. Plug the open end of hoses and pipes to prevent dust
from entering the hydraulic system.
Arm cylinder Removal
1. Operate arm cylinder (21) until it becomes slightly longer
than the fully retracted state.
2. Lower the boom and rest the end of the arm on the
ground.
3. Hoist and hold arm cylinder (21) with ropes.
Lightly support the cylinder without pulling on the crane
rope too tightly at this time.
Take care not to allow wire rope to slide on the cylinder.
4. Release remaining pressure from the piping of arm
cylinder (21).
Refer to the "Operator's Manual for Hitachi Excavator" for
releasing pressure.
5. Remove pin (24) connecting arm cylinder (21) and arm
(22).
6. Fully extend arm cylinder (21).
7. Slightly hoist wire rope. Place a wooden block on boom
(25). Slowly lower arm cylinder (21) onto the block.
DISASSEMBLING • ASSEMBLING
4-19
22
24
21
M1T1-SL1-001
21
25
M1T1-SL1-002