Oshkosh Corporation JLG 450AJ, Руководство по обслуживанию и ремонту

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SECTION 4 - BOOM & PLATFORM
3121659 – JLG Lift – 4-1
SECTION 4. BOOM & PLATFORM
4.1 BOOM MAINTENANCE
DO NOT USE A LIFTING DEVICE TO LIFT BOOMS UNLESS
HOLDING VALVES HAVE BEEN REMOVED FIRST. FAILURE
TO DO SO WILL RESULT IN SEVERE DAMAGE TO BOOM.
Remove Boom Assembly
1. Remove platform and platform support as follows:
a. Disconnect control console electrical cable.
b. Use an appropriately rated overhead crane or suit-
able lifting device and nylon support straps to sup-
port the platform/support.
NOTE: Properly support cylinder when removing retaining pin
from rod end of level cylinder.
c. Remove bolts and keeper pins from retaining pins.
Remove retaining pins from platform support using
suitable brass drift and hammer.
2. Remove boom from turntable as follows:
a. Disconnect wiring harness from ground control har-
ness connector.
CAP HYDRAULIC LINES AND PORTS IMMEDIATELY AFTER DISCONNECTING
LINES TO PREVENT ENTRY OF CONTAMINANTS INTO SYSTEM.
b. Tag and disconnect boom to control valve hydraulic
lines. Use a suitable container to retain residual
hydraulic fluid. Cap all hydraulic lines and ports.
c. Support boom weight along entire length with
appropriately rated lifting equipment.
d. Remove bolts and keeper pins from lift cylinder
pivot pin. Using a suitable brass drift and hammer,
remove pivot pin from lower boom.
NOTE: To gain access for removal of pivot pins, it may be neces-
sary to remove ground control box, hydraulic and fuel
tanks, and counterweight.
e. Remove retaining hardware from level link pivot
pin. Using a suitable brass drift and hammer,
remove pin from level link and turntable.
f. Remove hardware securing lower boom pivot pin.
Using a suitable brass drift and hammer, remove pin
from the turntable.
g. Using all applicable safety precautions, carefully lift
boom assembly clear of turntable and lower to
ground or suitable supported work surface.
Main Boom Disassembly
1. Loosen jam nuts on aft end of fly boom wear pad adjust-
ment and loosen adjustments.
2. Using a portable power source, attach hose to telescope
cylinder port block. Using all applicable safety precau-
tions, activate hydraulic system and extend cylinder to
gain access to cylinder rod retaining pin. Shut down
hydraulic system.
3. Carefully disconnect hydraulic hose from retract port of
cylinder. There will be initial weeping of hydraulic fluid
which can be caught in a suitable container. After initial
discharge, there should be no further leakage from the
retract port.
4. Remove hardware securing telescope cylinder to the fly
boom section, then remove pin from fly.
5. Remove hardware securing telescope cylinder to the
base boom section.
WHEN REMOVING TELESCOPE C YLINDER FROM BOOM SECTIONS. CARE
SHOULD BE TAKEN NOT TO LEAVE CYLINDER REST ON POWERTRACK WHICH
COULD CAUSE DAMAGE TO POWERTRACK.
6. Using a suitable lifting device, remove telescope cylin-
der from boom sections.
7. Using a piece of tape, mark length of hoses and wires
from front of fly boom and bottom of base boom for
reassembly.
8. Remove hardware securing front wear pads on base
boom section. Remove wear pads.
9. Remove hardware securing powertrack to aft end of fly
boom section.
10. Using a suitable lifting device, remove fly boom from
boom section.
11. Remove hydraulic lines and electrical cables from pow-
ertrack.
12. Remove hardware securing powertrack to base boom
section. Remove powertrack.