Tractor Repair: 856 International Hydraulics, auxiliary control, rear frame

Question
Auxiliary control valve and hydraulic lift system (3 point lift) has quit working on 856 International and I need to know what the problem might be.

Answer
Hello,

  The hitch and auxiliary are supplied by the rear hydraulic pump located in the rear frame, and the power steering, brakes, and TA are supplied by the front pump behind the MCV valve on the side of the clutch housing.  If everything quit working, the live power shaft that is driven by the clutch is not turning, either from stripped splines on the shaft, or sheared rivets on the clutch hub.  If steering, brakes, and TA still work, then the problem is with the rear pump, or the gear that drives it.  Plug a gauge into a remote coupler and see if there is any pressure.  If the pressure is low, it could be a bad relief valve.  If there is no pressure at all, either the rear pump has failed, or the drive gear or pump gear is broken and the pump is not turning.


                        Arnie