Secondary Boom Extension Cylinders - Genie ZX-135/70 Service And Repair Manual

April 2018
4-7
Secondary Boom Extension
Cylinders
The secondary boom extension cylinders extend
and retract the secondary boom. The secondary
boom extension system consists of 3 hydraulic
cylinders and each are equipped with
counterbalance valves to prevent movement in the
event of a hydraulic line failure.
How to Remove the Secondary
Boom Extension Cylinders
Bodily injury hazard. This
procedure requires specific repair
skills, lifting equipment and a
suitable workshop. Attempting
this procedure without these skills
and tools could result in death or
serious injury and significant
component damage. Dealer
service is strongly recommended.
Note: When removing a hose assembly or fitting,
the O-ring (if equipped) on the fitting and/or hose
end must be replaced. All connections must be
torqued to specification during installation. Refer to
Specifications, Hydraulic Hose and Fitting Torque
Specifications.
Note: Perform this procedure with the machine on
a firm, level surface and in the stowed position with
the axles extended.
Part No. 1279835GT
1 Raise the primary boom approximately 10 feet
/ 3 m. Turn the machine off.
2 Working at the platform end of the secondary
boom, support and secure the secondary
boom end cover to a suitable lifting device.
3 Remove the cover retaining fasteners and
remove the cover from the secondary boom.
4 Remove the retaining fasteners from both
secondary boom extend limit switches and
remove the limit switches. Do not disconnect
the wiring.
Note: Label the location of each limit switch as they
are not the same and their mounting locations
cannot be exchanged.
5 Tag, disconnect and plug all hydraulic hoses
for the 3 secondary boom extension cylinders.
Cap the fittings on the cylinder.
6 Remove the upper extension cylinder
retainers from the saddle blocks.
ZX®-135/70
Service and Repair Manual
Boom Components
Crushing hazard. The secondary
boom end cover could become
unbalanced and fall when
removed from the secondary
boom if not properly supported
and secured to the lifting device.
Bodily injury hazard. Spraying
hydraulic oil can penetrate and
burn skin. Loosen hydraulic
connections very slowly to allow
the oil pressure to dissipate
gradually. Do not allow oil to
squirt or spray.
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