Platform Leveling Master Cylinder - Genie Z-30/20N Service Manual

Section 4 • Repair Procedures
PRIMARY BOOM COMPONENTS
5 Remove the primary boom extend drive limit
switch from the pivot end of the primary boom.
Do not disconnect the wiring.
6 Remove the retaining fastener from the master
cylinder rod-end pivot pin. Use a soft metal drift
to remove the pin.
7 Manually retract the master cylinder and push it
toward the platform end of the boom to obtain
enough clearance for extension cylinder
removal.
8 Tag, disconnect and plug the extension cylinder
hydraulic hoses. Cap the fittings on the
cylinder.
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.
9 Remove the retaining fastener from the
extension cylinder barrel-end pivot pin. Use a
soft metal drift to remove the pin.
10 Carefully pull out and properly support the
extension cylinder from the primary boom with
a lifting strap from an overhead crane.
Crushing hazard. The cylinder
could fall if not properly supported
when it is pulled out of the
extension tube.
Note: To make installation of the extension cylinder
easier, be sure that the cylinder rod is extended
3 to 4 feet / 1 m.
Note: During removal, the overhead crane strap will
need to be carefully adjusted for proper balancing.
4 - 20 Z-30/20N • Z-30/20N RJ • Z-34/22 • Z-34/22N
4-5
Platform Leveling Master
Cylinder
The platform leveling master cylinder acts as a
pump for the slave cylinder. It is part of the closed-
loop hydraulic circuit that keeps the platform level
through the entire range of primary boom motion.
The platform leveling master cylinder is located
inside the upper mid-pivot at the pivot end of the
primary boom.
How to Remove the Platform
Leveling Master 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.
Note: 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.
Note: Before cylinder removal is considered, bleed
the cylinder to be sure that there is no air in the
closed loop. See 2-1, How to Bleed the Slave
Cylinder.
June 2011
REV A
Part No. 139378