REPAIR PROCEDURES
TB18 Plus&20J Plus Maintenance Manual 6-3 © Apr 2022
Jib Boom Assembly(TB20J Plus
only)
MOVING OBJECT HAZARD
Wear eye protection when tapping
the brass drift with wooden hammer.
Figure 6-3
Removing the jib boom assembly
NOTICE
When removing the hose and fitting, the O-ring on
the fitting and hose end must also be removed and
tagged.
1. Position the main boom horizontal, and attach the
jib boom assembly to a suitable crane.
2. Use a suitable device to support the upper level
cylinder.
3. Remove the fasteners at the pivot pin 1# of upper
level cylinder, and drive the pivot pin 1# out using
brass drift and wooden hammer.
4. Remove the fasteners at the pivot pin 2#, and drive
the pivot pin 2# out using brass drift and wooden
hammer.
5. Using the crane, slowly lift the jib boom assembly
off the main boom.
Inspecting the jib boom assembly
NOTICE
When inspecting the pins and bearings, please see
Pins and composite bearing, page 4-5.
• Check the pivot pins for wear,scratch, deformation
or other damages, and replace if needed.
• Check the inside of bearings for eear, scratch,
deformation or other damages, and replace if
needed.
• Check the jib lift cylinder connecting pins for wear,
scratch, deformation or other damages. Before
installation, ensure the pin surface is treated with
protection. Replace if needed.
• Check the inside of the bearings connecting the
platform rotate motor for wear, scratch, deformation
or other damages, and replace if needed.
• Check all threaded parts for elongation, thread
deformation, torsion or other demages, and replace
if needed.
• Check all structures of jib boom assembly for
deformationm, cracks, weld detachment or other
damages, and replace the jib boom if needed.
Platform Level Cylinder
MOVING OBJECT HAZARD
Wear eye protection when tapping
the brass drift with wooden hammer.
NOTICE
When removing the cylinder, special care should be
taken to avoid the fall of the cylinder and component
damage.
The machine is configured with 2 platform level
cylinders located at the boom upper end and lower end.
The platform level cylinder is used for maintaining the
platform level (in relation to the turntable) through the
entire range of motion.
1. Extend the boom until the platform level cylinder
rod-end pivot pin is accessible.
2. Slightly raise the boom and place a support under
the platform.
3. Lower the boom until the platform sits on the
support. Take special care not to press the total
weight of boom over the support.