Secondary Boom Lift Cylinders - Genie Z-45/25 Service Manual

March 2005
REV A
5-2

Secondary Boom Lift Cylinders

There are two secondary boom lift cylinders
incorporated in the structure of the secondary boom
assembly. These cylinders operate in parallel and
require hydraulic pressure to extend and retract.
Each secondary boom lift cylinder is equipped with
a counterbalance valve to prevent movement in the
event of a hydraulic line failure.
How to Remove a Secondary
Boom Lift Cylinder
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.
When removing a hose assembly
or fitting, the O-ring on the fitting
and/or hose end must be replaced
and then torqued to specification
during installation.
Refer to Section 2, Hydraulic Hose
and Fitting Torque Specifications.
1 Lower the secondary boom to the stowed
position.
2 Raise the primary boom so that it is above the
secondary boom lift cylinder rod-end pivot pin.
Part No. 77809
3 Tag, disconnect and plug the hydraulic hoses
on the secondary boom lift cylinder.
4 Remove the pin retaining fasteners from the
secondary boom lift cylinder rod-end pivot pin
and barrel-end pivot pin. Do not remove the
pins.
5 Attach a strap from an overhead crane to the lug
on the rod end of the secondary boom lift
cylinder for support. Do not apply any lifting
pressure.
6 Use a soft metal drift to drive the barrel-end
pivot pin half way out. Lower the barrel end of
the secondary boom lift cylinder and let it hang
down.
7 Use a soft metal drift to drive the rod-end pivot
pin half way out.
8 Remove the secondary boom lift cylinder from
the machine.
Genie Z-45/25 and Genie Z-45/25J
Section 4 • Repair Procedures
SECONDARY BOOM COMPONENTS
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.
Crushing hazard. The secondary
boom lift cylinder could become
unbalanced and fall when removed
from the machine if not properly
attached to the overhead crane.
Component damage hazard. When
removing a secondary boom lift
cylinder from the machine, be
careful not to damage the
counterbalance valve at the barrel
end of the cylinder.
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