April 2017 Service and Repair ManualTransmissionPart No. 1272854 GTH-844 436-1Hydraulic PumpHow to T est the Func tion PumpHow to Test the Function PumpNote: 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.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.1 Connect a 0 to 5000 psi / 0 to 350 barpressure gauge to port TP on the secondaryfunction manifold.2 Start the engine and fully retract the boom.Continue to hold the joystick in the boomretract position and observe the pressuregauge.Result: If the pressure gauge reads 3200 psi /220 bar, immediately stop. The pump is good.Result: If the pressure fails to reach 3200 psi /220 bar, the pump needs to be adjusted OR orthe pump or pump coupling is faulty and willneed to be serviced or replaced.Component damage hazard.There is no relief valve in thehydraulic pump and the pumpcan be damaged if the pressureis allowed to exceedspecification. When testing thepump, crank the engine in onesecond intervals until thecorrect pressure is confirmed.Do not over-pressurize thepump.3 Remove the pressure gauge and install plugonto port TP. Torque to specification. Refer toSection Specifications, HydraulicSpecifications.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.
