Hello sk120-5 sn LP16476 displayed mechantro cpu fail for a few moments then no text on display I put in a new china controller same pn but display has no text This is a rough machine with a hand throttle but it operates the same before and after the cpu fail message and change of controller Its faults include slow slew unless you operate the crowd etc at the same time and one slow track motor. I am gong to fit a new pump servo valve but do have burred cap head retaining screws on the valves thanks
Hi, no text on the display is probably just a faulty screen(common problem in those machines). If you have fitted a new controller it needs to be calibrated but if there is a hand throttle in the machine it can't be done. You need the stepper motor connected and adjusted correctly to carry out the calibration/A adjustment. Which track is slow. If slew and left track are slow it could be a number of things including pump solenoid, high pressure sensor, by pass solenoid.
Thanks for advice I put in a new screen but no display just horizontal line and beeping Removed switchbox and found circuit board had shorting due to wet quarry dust in switchbox. Cleaned up board and reinstalled but no lcd so disconnected plugs to controller Excavator did operate but poorly then gradually got worse with noise from pump and track motors v weak Removed hydraulic pump overhauled w new valve plates bearings swashplates and housings rotating groups pilot pump drive coupling Reinstalled pump and ran ( pilot at 500 psi ) and no real hydraulic action removed valve block and able to move servo pistons and 24v at pump valves This is what I get at present -boom up and stick out weak w pump noise -slew slow but working no pump noise -tracks and crowd no real try and no pump noise any help appreciated