4 - 74 S-100 • S-105 • S-120 • S-125 Part No. 102916June 2011Section 4 • Repair ProceduresREV AHYDRAULIC PUMPS9-3Auxiliary PumpHow to Test the Auxiliary PumpThe auxiliary pump is a 2-section, gear-type pump.Pump number 1 is the pump section closest to thepump motor and pump number 2 is the pumpsection that is farther from the pump motor. Eachsection of the pump has its own relief valve locatedwithin the pump body.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 Two,Hydraulic Hoseand Fitting Torque Specifications.1 Disconnect and plug the high pressure hydraulichose from pump number 1.Bodily injury hazard. Sprayinghydraulic oil can penetrate andburn skin. Loosen hydraulicconnections very slowly to allowthe oil pressure to dissipategradually. Do not allow oil to squirtor spray.2 Connect a 0 to 5000 psi / 0 to 345 bar pressuregauge to the high pressure port on pumpnumber 1.3 Turn the key switch to ground control and pullout the Emergency Stop button to the ONposition.4 Activate any function using auxiliary power.Result: If the pressure gauge reads 2500 psi /172 bar, immediately stop. The pump is good.Result: If pressure fails to reach 2500 psi/ 172 bar, the internal relief valve setting isincorrect or the pump is bad and will need to beserviced or replaced.5 Turn the key switch to the OFF position.6 Remove the pressure gauge and reconnect thehydraulic hose.7 Disconnect the hydraulic hose from the highpressure port from pump number 2.8 Connect a 0 to 5000 psi / 0 to 345 bar pressuregauge to the high pressure port on pumpnumber 2.9 Turn the key switch to ground control and pullout the Emergency Stop button to the ONposition.10 Activate any function using auxiliary power.Result: If the pressure gauge reads 3000 psi /207 bar, immediately stop. The pump is good.Result: If pressure fails to reach 3000 psi/ 207 bar, the internal relief valve setting isincorrect or the pump is bad and will need to beserviced or replaced.11 Remove the pressure gauge and reconnect thehydraulic hose.
