Jib; Removal; Disassembly; Inspection - JLG H340AJ Service And Maintenance Manual

4.5 JIB

Removal

1. Lower the jib and platform assembly to the ground or
onto blocking to support the weight of the jib.
HYDRAULIC LINES AND PORTS SHOULD BE CAPPED IMMEDIATELY AFTER DIS-
CONNECTING LINES TO AVOID ENTRY OF CONTAMINANTS INTO SYSTEM.
2. Tag and disconnect hydraulic lines from level cylinder
and lift cylinder. Use suitable container to retain any
residual hydraulic fluid. Cap hydraulic lines and ports.
3. Attach an adequate supporting device to the lift cylin-
der assembly to support its weight.
4. Remove bolt and pin keeper securing level cylinder
assembly. Using a suitable brass drift and hammer,
remove the cylinder pin from jib assembly.
5. Place blocking under the cylinder rod or a soft material
under the cylinder rod to protect the rod from being
scratched.
NOTE: The jib and platform assembly weighs approximately
121.9 lbs. (55.3 kg.).
6. Attach an adequate supporting device to the jib and
platform assembly to support its weight.
7. Remove bolt and pin keeper securing jib and platform
assembly to the boom sections. Using a suitable brass
drift and hammer, remove the pin from jib and platform
assembly.
8. Remove the jib and platform assembly from the boom.
3121634

Disassembly

1. Remove bushings and mounting hardware from jib
pivot pin. Using a suitable brass drift and hammer,
remove the pin from jib pivot.
2. Remove bushings and mounting hardware from jib
boom pivot pin of the lift cylinder assembly. Using a
suitable brass drift and hammer, remove the pin from jib
pivot.
3. Remove the jib pivot from jib and platform assembly.
4. Attach an adequate supporting device to the lift cylin-
der assembly to support its weight.
5. Remove mounting hardware from cylinder pin of the lift
cylinder assembly. Using a suitable brass drift and ham-
mer, remove the pin from the lift cylinder assembly.
6. Carefully remove the lift cylinder assembly from jib and
platform assembly.
7. Remove mounting hardware from rotator pin. Using a
suitable brass drift and hammer, remove the pin from
the rotator.
8. Remove rotator from jib and platform assembly.

Inspection

NOTE: When inspecting pins and bearings Refer to Section 2.5 -
Pins and Composite Bearing Repair Guidelines.
1. Inspect fly boom pivot pin for wear, scoring, tapering
and ovality, or other damage. Replace pins as necessary.
2. Inspect fly boom pivot attach points for scoring, taper-
ing and ovality, or other damage. Replace pins as neces-
sary.
3. Inspect inner diameter of fly boom pivot bearings for
scoring, distortion, wear, or other damage. Replace bear-
ings as necessary.
MAE16060
4. Inspect lift cylinder attach pin for wear, scoring, tapering
and ovality, or other damage. Ensure pin surfaces are
SECTION 4 - BOOM & PLATFORM
MAE16080
4-15