Even a well-manufactured hydraulic system will begin to malfunction at some point, requiring a repair or replacement.
It’s possible hydraulic fluid has been contaminated or perhaps the machine has been used outside of the manufacturer’s specifications. What if maintenance was never performed, or a faulty component has now failed?
Once a system failure takes place, beginning the process of troubleshooting the system is essential. Staying organized and methodical is the key to proper and effective troubleshooting of a hydraulic system.
When a problem is reported with the machinery, the first step is to review the failure with the machine operator (if available). Did the machine slow at a particular moment of use? Was there grinding or winch speed trouble? Is the motor moving too quickly? Does the motor stall while lifting a heavy load?
Details will emerge naturally as the operator explains the failure, but feel free to explore and inquire as you talk it through. Time may have passed since the operator experienced trouble and you (the troubleshooter, or a mechanic) have had a chance to address it. Be patient as you investigate, and take notes during the interview.
The first step is to find out if the problem with the machine was a problem with the person operating the machine. Is there a function the driver isn’t aware of? Can you take the machine out to test the settings yourself? This is always step one of the troubleshooting process: confirmation of the fault so you know it really is a mechanical problem with this machine. If a failure can’t be confirmed, then operator training or redeployment of the machine may be in order.
Once a failure is confirmed, establishing the timeline for repair is important. Any time lost is often money lost. Consider doing the repair on-site if this is feasible based on the conditions and weather.
While you continue to search for the root of the system failure, you should start simple by troubleshooting one step at a time. The “shotgun approach” (attempting multiple repairs at once may fix the problem, but you may never figure out what the problem actually was!
Some simple tasks to begin with after a malfunction are:
- Look for an external leak.
- Look for loose connectors.
- Check the hydraulic fluid.
- Check the filters.
Once the easier troubleshooting is complete, the next step is a battle plan for the rigorous testing. Because the hydraulic system is essentially a circuit, follow the flow of the system and look for leaks or failures. Refer to the system schematic diagram for help.
Now look for internal leaks caused by failed pistons, seals or valves. Any of these leaks cause fluid to accumulate in areas it doesn’t belong, leading to flooding and system slow-flow or failure. Flow of the hydraulic system tends to back-flow when it leaks, carrying the hydraulic fluid back into the tank and leading to a breakdown.
The schematic diagram can offer clues to electrical failure as well. Check voltages and power flow on the machine and electrical solenoids, as testing them is a relatively short process. Check for scratches or scuffing on or around the pistons of a machine to see if there is any alignment problem.
Finally, when the hydraulic system failure is finally identified and repaired on a machine, determine if further action is required to prevent this problem from occurring again. Did operator error lead to this, and should operators be warned to avoid failures in the future? Was failure due to normal wear and tear?
Using this process of troubleshooting, you should be able to determine the root cause of your hydraulic system failure and quickly get your machines repaired and operating in the field as quickly as possible.