September 2016 Service ManualHydraulic Power UnitPart No. 38139 AWP Super Series • IWP Super Series 873-6 H ydr aulic Pump3-6Hydraulic PumpHow to Remove the HydraulicPumpNote: 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 Fully lower the platform.2 Turn the key switch off and disconnect thepower supply.3 IWPS models: Pull the base lowering handleto fully lower the base.4 Remove the power unit cover.5 Remove the power unit. See 3-4, How toRemove the Power Unit.6 Support the hydraulic tank with a lifting device.7 Remove the mounting fasteners from the tank.Remove the tank from the power unit. Do notallow the hydraulic oil to spill.Note: It may be necessary to tap the side of thetank with a soft rubber mallet to loosen it.8 Remove the mounting fastener from thesuction cover assembly on the pump. Thenremove the suction cover.9 Remove the mounting fasteners from thepump. Then remove the pump from the powerunit.Note: When installing the tank, be sure not todamage the o-ring.3-7 Valve Adjus tment3-7Valve AdjustmentHow to Adjust the Platform LiftRelief ValveNote: Be sure the hydraulic oil level is between theFULL and ADD marks on the oil level indicator.1 Remove the power unit cover.2 Loosen the locknut on the relief valve locatedon the right side of the motor.3 Follow the appropriate operator's manual toset up the machine for operation.4 Place maximum rated load into the platform.Secure the load to the platform. Refer toSpecifications, Machine Specifications.5 Hold the relief valve screw and loosen the locknut.6 While activating the platform up function, turnthe relief valve screw clockwise, just until theplatform begins to raise.7 Fully lower the platform.8 Add additional weight to the platform that isequal to, but does not exceed 20% of themaximum rated load. Secure the additionalweight. Refer to the machine serial plate.
