Hydraulics Troubleshooting Tips Cheat Sheet

Finding and solving problems

1. SYSTEM INOPERATIVE
• No oil in the system, insufficient oil in the system. Fill system. Check for leaks.
• Wrong oil in the system. Refer to specifications. Change oil.
• Filter dirty or clogged. Drain oil and replace the filter or filter element.
• Oil line restriction. Oil lines are dirty or collapsed. Clean or replace.
• Air leaks in pump suction line. Repair or replace as necessary.
• Worn or dirty pump. Clean, repair, or replace. Check alignment. Check for contaminated oil. Drain and flush system.
• Badly worn components (valves, cylinders, etc.) Examine and test for internal or external leakage. Replace faulty components. Check for cause of wear.
• Leakage. Check all components, particularly the relief valve, for proper settings. Refer to technical manuals.
• Excessive load. Check unit specifications for load limits.
• Slipping or broken pump drive. Repair or replace belts, couplings, etc. Check for proper alignment or tension.

2. SYSTEM OPERATES ERRATICALLY
• Air in the system. Check the suction side of the system for leaks. Repair.
• Cold oil. Allow ample warm-up period.
• Dirty or damaged components. Clear or repair as necessary.
• Restrictions in filters or lines. Clean and/or replace elements or lines.

3. SYSTEM OPERATES SLOWLY
• Oil viscosity is too high; cold oil. Allow the oil to warm up before operating the machine.
• Low pump drive speed. Increase engine speed (check the manual for recommendations.)
• Air in the system. Check the suction side for leaks. Repair.
• Badly worn pump, valves, cylinders, etc. Repair or replace as needed.
• Restrictions in filters or lines. Clean and/or replace elements or lines.
• Improper adjustments. Check orifices, relief valves, etc. Adjust per manual.
• Oil leaks. Tighten fittings. Replace seals or damaged lines.

4. SYSTEM OPERATES TOO FAST
• Wrong size or incorrectly adjusted restrictor. Replace or adjust as necessary.
• Engine running too fast. Reduce engine speed.

5. OVERHEATING OF OIL IN THE SYSTEM
• Oil passes through the relief valve for an excessive amount of time. Return the control valve to neutral when not in use.
• Incorrect oil, low oil, dirty oil. Use recommended oil, fill the reservoir, clean oil, and replace filter elements.
• Engine running too fast. Reduce engine speed.
• Excessive component internal leakage. Repair or replace components as necessary.
• Restriction in filters or lines. Clean and/or replace elements or lines.
• Malfunctioning oil cooler. Clean or repair.

5. OVERHEATING OF OIL IN SYSTEM (cont’d.)
• Insufficient heat radiation. Clean dirt and mud from the reservoir and components.
• Malfunctioning component. Repair or replace.
• Reservoir too small. The recommended size is 1 1/2 times the pump gpm.

6. FOAMING OF OIL
• Incorrect, low, or dirty oil. Replace, clean, or add oil as needed.
• Air leaks. Check the suction line and component seals for suction leaks. Replace.

7. NOISY PUMP
• Low oil level, incorrect oil, foamy oil. Replace, clean, or add oil as needed.
• The suction line is plugged or too small, and the inlet screen is plugged. Clean or replace. Follow the instructions packed with the unit.
• Use a pipe fitting in the inlet. Replace with correct fitting.

8. BLOWN SHAFT SEAL
• Pump: wrong pump shaft rotation. Replace seal. Refer to installation instructions.
• Motor: failure to hook up the drain line. Replace seal. Refer to installation instructions.

9. LEAKY PUMP OR MOTOR
• Damaged or worn shaft seal. Replace seal. Check for misalignment.
• Loose or broken parts. Tighten or replace.

10. LOAD DROPS WITH CONTROL VALVE IN NEUTRAL
• Leaking cylinder seals or fittings. Replace worn parts.
• Control valve not centering when released. Check linkage. Check for spool binding. Repair.

11. CONTROL VALVE DOES NOT CENTER (Binding)
• See the Hydraulic Product Safety sheet.
• Valve linkage misaligned. Repair.
• Tie-bolts too tight (stack valves). Loosen as necessary.
• Valve damaged. Repair or replace.
• Handle bracket screws loose. Tighten.

12. CONTROL VALVE LEAKS EXTERNALLY
• Tie-bolts too loose (stack valves). Tighten as necessary.
• Seals damaged or worn. Replace.
• Back pressure or restriction in tank line. Check quick couplers. Use power beyond when necessary.
• Cracked port or body. Replace. (see Hyd. Prod. Safety)

13. CYLINDER LEAKS EXTERNALLY
• Seals damaged or worn. Replace.
• Rod damaged. Replace.

14. THE CYLINDER LOWERS WITH THE VALVE IN THE “METER UP” POSITION
• Damaged or leaky load check. Replace check.
• Leaking cylinder seal. Replace seal.
• Use of a valve without loadcheck. Replace with the recommended valve.