New Holland WORKMASTER 35, Operator'S Manual

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8 - TROUBLESHOOTING
Problem
Possible Cause Correction
Control valve failure Repair or replace valve
Hydraulic lift cylinder damaged Repair cylinder as needed
Lift shaft moving parts damaged Repair or replace lift shaft parts as needed
Steering - Troubleshooting
Problem Possible Cause Correction
Hydraulic steering system
does not work Faulty power steering pump Replace pump if needed
Steering unit damaged or worn Repair or replace unit as needed
Steering cylinder piston seal damaged or
worn Repair cylinder as needed
External oil leakage of oil tubes or hoses
Repair or replace tubes or hoses as
needed
Excessive steering wheel
effort Steering unit: Spline and column spline
does not align Check mounted condition of steering unit
and column
Steering unit: Spool and sleeve damaged
by foreign material Replace steering unit
Steering unit: Excessive tightening torque
of end cap bolt Apply proper torque of end cap hardware
Pump: Low flow Increase engine RPM, to increase pump
flow
Faulty power steering pump Check pump , repair or replace if needed
Power steering relief valve: pressure set-
ting low Check power steering relief valve pressure
adjust to proper pressure setting
Cylinder movement not as
smooth as steering wheel Air in steering line if not used for a long time Bleed air in steering system
Air in suction tube Check suction tube, repair as needed
Cylinder piston seal damaged Repair cylinder as needed
Front wheels turn the
opposite direction to the
steering wheel direction Incorrect assembly of steering gear Repair steering gear as needed
Incorrect assembly of steering hoses Assemblel steering hoses correctly
Oil leakage of steering
pump, steering unit,
cylinder Seal damaged Replace seal
Abnormal noise Lack of oil Add oil as needed
Restriction of oil flow in suction line Replace filter
Air in system
Bleed air from system
Hydrostatic transmission - Troubleshooting
Problem Possible Cause Correction
When operating HST
pedal, tractor does not
move. HST high pressure relief valve pressure
setting low Check HST pressure and repair as needed
HST charge pressure valve faulty Check HST charge pressure and repair as
needed
HST Filter clogged Replace HST filter
HST pump faulty Repair or replace HST pump
HST control linkage worn or damaged
Repair or replace linkage as needed
Tractor is still moving
when HST pedal is in
neutral position Incorrect neutral adjustment of HST linkage Adjust neutral position of HST linkage
HST pedal linkage damaged Replace damaged linkage parts as needed
HST control arm clamp bolt loose Tighten control arm clamp bolt
HST power is low Oil shortage
Add transmission oil as needed
Air in HST circuit Check and repair the hydraulic suction line
8-3