Winch "chatters" while raising rated load.

1. System relief valve may be set too low. Relief valve needs adjustment or repair.

   Check relief pressure as follows:
   
   

   1. Install an accurate 0-4000 psi (27,580 kPa) gauge into the inlet port of the brake valve.
      
   2. Apply a stall pull load on the winch while monitoring pressure.
      
   3. Compare gauge reading to winch specifications. Adjust relief valve as required.
      

   
   NOTE: If pressure does not increase in proportion to adjustment, relief valve may be contaminated or worn out. In either case, the relief valve may require disassembly or replacement.

2. Hydraulic oil flow to motor may be too low.
   1. Plugged heat exchanger.

      Thoroughly clean exterior and flush interior.

   2. Too low or too high oil level in hydraulic reservoir.

      Fill/drain to proper level.

   3. System relief valve may be set too low. Relief valve needs adjustment or repair.

      Check relief pressure as follows:
      
      

      1. Install an accurate 0-4000 psi (27,580 kPa) gauge into the inlet port of the brake valve.
         
      2. Apply a stall pull load on the winch while monitoring pressure.
         
      3. Compare gauge reading to winch specifications. Adjust relief valve as required.
         

      
      NOTE: If pressure does not increase in proportion to adjustment, relief valve may be contaminated or worn out. In either case, the relief valve may require disassembly or replacement.

3. Hydraulic pump not operating efficiently.

   Prime mover low on horsepower or R.P.M. Tune/adjust prime mover. Check suction line for damage.
   
   If pump is belt driven, belts are slipping. Replace/tighten belts.
   
   Pump worn. Replace pump.

4. Controls being operated too quickly.

   Conduct operator training as required.