Practical hydraulic troubleshooting resources for technicians who need to determine why a system isn't working — not just which part might be bad.
A basic hydraulic system can be viewed as a path: reservoir → pump → control → actuator → return. Troubleshooting is the process of finding where that path stops behaving correctly.
Think system-wide: pump output, drive speed, oil supply, suction restriction, aeration, bypass, viscosity, or pump wear.
Determine whether the system reaches required pressure under the approved test condition. Check relief behavior, pump condition, bypass, and controls.
If the rest of the machine is normal, focus on the affected branch: valve, restriction, actuator, load control, electrical command, or mechanical load.
Compare cold and operating-temperature behavior. Increased leakage through worn clearances often becomes easier to see as viscosity drops.
Heat is wasted energy. Look for bypass, restrictions, backpressure, internal leakage, cooling problems, and incorrect fluid.
Verify the electrical command and then the hydraulic response. Power, ground, voltage drop, coil condition, spool movement, and circuit pressure all matter.
Know what the measurement should prove. Pressure measures force potential. Flow drives speed. Temperature exposes energy loss. Voltage drop verifies electrical delivery under load.