Return to Master Table of Contents Page 26 Hydraulic System Troubleshooting, Testing and Adjustment Problem Possible Causes Remedies Sluggish performance of all hydraulic functions - attachment, swing and travel. Main pump(s) damaged or worn Repair or replace Main relief valve pressure off Readjust pressure Low oil level in hydraulic system Refill Hydraulic reservoir intake strainer clogged Clean Pump inlet (supply side) piping or hose allowing air into hydraulic system Tighten connection Oil temperature abnormally high.
Oil cooler clogged or air circulation to cooler blocked Clean Cooling fan belt tension too loose Readjust belt tension Relief valve set too low Readjust valve Relief valve in constant use Reduce or slow work load or cycling rate Hydraulic oil severely neglected or incorrect for application Replace oil One circuit in hydraulic system inoperable.
Overload relief valve malfunction Readjust or replace Oil leak at make-up valve Clean, repair Control valve spool damaged Repair or replace Dirt in control valve spool Clean or replace Actuator (joystick, foot pedal) damaged or worn Repair or replace Internal seal leak in cylinder Repair or replace Cylinder rod damaged Repair or replace Pilot valve or piping malfunction Repair or replace Mechanical linkage frozen, loose or damaged Repair or replace Travel motors inoperable. Center joint damaged. Repair or replace. Parking brake not releasing. Repair or replace. Travel motor worn or damaged. Repair or replace. Travel motor pilot piping damaged. Repair or replace.
Travel motors operate very slowly. Track tension poorly adjusted Low oil in idlers or rollers. Readjust tension Refill. Travel brake dragging. Repair Track frame out of alignment, deformed or twisted. Repair Swing motor inoperable. Swing brake not releasing. Repair or replace Relief valve malfunction. Repair or replace Pilot piping damaged. Repair or replace