Service Manual February 2017Boom Components106 S-80 • S-85 • S-80X Part No. 1259369GT4-6Platform Leveling MasterCylinderThe master cylinder acts as a pump for the slavecylinder. It is part of the closed loop hydraulic circuitthat keeps the platform level through the entirerange of boom motion. The master cylinder islocated inside the pivot end of the boom.How to Remove the PlatformLeveling Master CylinderNote: When removing a hose assembly or fitting,the O-ring (if equipped) on the fitting and/or hoseend must be replaced. All connections must betorqued to specification during installation. Refer toSpecifications, Hydraulic Hose and Fitting TorqueSpecifications.1 Raise the boom until the master cylinderrod-end pivot pin is accessible.2 Remove the turntable end cover to access themaster cylinder.3 Tag, disconnect and plug the master cylinderhydraulic hoses. Cap the fittings on thecylinder.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 pin retaining fastener from themaster cylinder barrel-end pivot pin.5 Place a rod through the barrel-end pivot pinand twist to remove the pin.6 Attach a lifting strap from an overhead craneto the lug on the rod end of the mastercylinder.7 Remove the pin retaining fastener from therod-end pivot pin.8 Place a rod through the rod-end pivot pin andtwist to remove the pin.9 Remove the master cylinder from themachine.Crushing hazard. The mastercylinder could becomeunbalanced and fall if notproperly attached to theoverhead crane.
