Danfoss K Frame Series Service Manual

Contents

Danfoss K Frame Series Service Manual Manual pdf 14 page image

Excessive noise and/or vibrationItem Description ActionCheck oil level in reservoirand oil supply to the motor.Insufficient hydraulic fluid could lead to cavitation thatwould cause system noise.Fill the reservoir to the proper level and ensure that oilsupply to the motor is adequate and the lines areunobstructed.Check for air in the system. Air trapped within the system lines, or the motor itself,could result in cavitation that would cause system noise.Ensure that all of the system lines and components arepurged of air.Inspect the output shaftcouplings.A loose or incorrect shaft coupling will produce vibrationsthat could result in system noise.Ensure that the correct coupling is used and that it fitsproperly onto the shaft.Inspect the output shaftalignment.Misaligned shafts create excessive frictional vibration thatcould result in system noise.Ensure that the shafts are properly aligned.Hydraulic oil viscosity abovelimits.Viscosity above acceptable limits will result in cavitationthat would lead to system noise.Replace hydraulic oil with appropriate fluid for operatingconditions. Refer to publication 5200L0463 for informationon fluid selection.System operating hotItem Description ActionCheck oil level in reservoirand oil supply to the pump.Insufficient amount of hydraulic fluid will not meet thecooling demands of the system.Fill the reservoir to the proper level.Inspect the heat exchanger,(if so equipped).If the heat exchanger fails, or becomes obstructed, it maynot meet the cooling demands of the system.Ensure that heat exchanger is receiving adequate air flowand that the heat exchanger is in good operatingcondition. Repair or replace as necessary.Check the system reliefvalves.If a system relief valve becomes unseated for an extendedperiod of time or fails for any other reason, the systemcould become overheated.Repair or replace any malfunctioning relief valves asapplicable and verify that the loads on the machine are notexcessive.Motor shifting irregularitiesItem Description ActionCheck the electricalconnection and electricalsignal to the shifting valvecoil.Electrical signal is needed to energize the valve coil. Theenergized coil is shifting the motor.Ensure that the electrical connection between controllervalve coil is alright. Check wires and connectors. Checkelectric signal. Valve coil can be energized with 12V PWM-signal or directly with 12V.Check valve coil The energized valve coil is moving the valve spool. Thatleads to motor shifting.Measure valve coil resistance. Value needs to be 5,3ohms+-5%. Replace valve if resistance is differing.Check shifting pressure. Shifting pressure moves servo piston. Obstruction couldresult in slow or no shift conditions.Shifting pressure at full energized valve coil (1500mA)needs to be at 20-32bar [290-464psi] or system inputpressure, whichever is lower. Replace shifting valve whenmeasured pressure is differing.Service ManualK and L Frame Variable Motors, Cartridge MountTroubleshooting14 | © Danfoss | July 2017 520L0631 | AX00000042en-US0402