Genie Z-30/20N Service Manual

Also see for Z-30/20N: Maintenance manual Maintenance manual Service manual Service and repair manual Service manual

Contents

Genie Z-30/20N Service Manual Manual pdf 54 page image

4 - 4 Z-30/20N • Z-30/20N RJ • Z-34/22 • Z-34/22N Part No. 139378June 2011Section 4 • Repair ProceduresREV A2-1Platform Leveling Slave CylinderThe slave cylinder and the rotator pivot are thetwo primary supports for the platform. The slavecylinder keeps the platform level through theentire range of primary boom motion. It operates ina closed loop hydraulic circuit with the mastercylinder. The slave cylinder is equipped withcounterbalance valves to prevent platformmovement in the event of a hydraulic line failure.How to Remove the SlaveCylinderNote: Before cylinder removal is considered, bleedthe slave cylinder to be sure there is noair in the closed loop hydraulic circuit.Note: When removing a hose assembly or fitting,the O-ring on the fitting and/or hose end must bereplaced and then torqued to specification duringinstallation. Refer to Section 2,Hydraulic Hose andFitting Torque Specifications.1 Extend the boom until the slave cylinderbarrel-end pivot pin is accessible.2 Raise the boom slightly and place blocks underthe platform for support. Lower the boom untilthe platform is resting on the blocks.3 Tag and disconnect the hydraulic hoses to theslave cylinder at the union and connect themtogether with a connector. Cap the fittings onthe cylinder hoses.Bodily injury hazard. Sprayinghydraulic oil can penetrate andburn skin. Loosen hydraulicconnections very slowly to allowthe oil pressure to dissipategradually. Do not allow oil tosquirt or spray.4 Remove the external snap rings from therod-end pivot pin. Do not remove the pin.5 Remove the external snap rings from thebarrel-end pivot pin.6 Place a block of wood under the barrel of theslave cylinder for support.7 Use a soft metal drift to remove the rod-endpivot pin.Crushing hazard. The platformcould fall if not properly supported.8 Use a soft metal drift to remove the barrel-endpivot pin.9 Carefully pull the cylinder with hydraulic hosesout of the boom.Crushing hazard. The slavecylinder could fall if not properlysupported.How to Bleed the Slave Cylinder1 Raise the jib boom to a horizontal position.2 Move the platform level toggle switch up anddown through two platform leveling cycles toremove any air that might be in the system.Platform Components