Hydraulic Pump Troubleshooting
When your hydraulic pump isn’t building pressure, it can result in costly downtime and operational delays. However, before assuming the pump is faulty, it’s important to systematically troubleshoot the system. By following a structured approach, you can identify and potentially resolve the issue without the need for expensive repairs or replacements. This guide offers a step-by-step checklist to help you troubleshoot pressure problems in your hydraulic pump.
Hydraulic Pump No-Pressure Troubleshooting Checklist
1. Verify Directional Control Settings
Start with the basics, checking the directional control settings. In busy work environments, settings can sometimes be accidentally altered without anyone noticing. If the directional control valve is not set correctly, your hydraulic pump may not build pressure. Whether your controls are manual or solenoid-operated, ensure the valve is positioned properly to prevent unnecessary troubleshooting and save time.
2. Ensure Adequate Fluid Supply
A hydraulic pump relies on a steady flow of fluid. Various factors can obstruct this flow, so it’s critical to check for the following issues:
- Air Leaks: Inspect the suction line for any air leaks that could cause cavitation and interrupt fluid flow.
- Startup Air: Make sure there’s no trapped air in the pump at startup, as this can prevent pressure build-up.
- Fluid Levels: Verify that the reservoir has enough oil. Low fluid levels can result in cavitation, which hinders pressure generation.
- Filter and Line Blockages: Examine the filters, inlet lines, and reservoir breather vent. Any blockages here can restrict fluid flow, preventing the pump from functioning properly.
3. Check Drive Motor Direction
A common issue is the drive motor running in reverse due to incorrect installation. If the motor is turning in the wrong direction, it will reverse the fluid flow and cause pressure problems. After confirming that the directional control valve is set correctly, check the motor’s rotation. Correct any mismatches in piping or control valve connections that could lead to reverse operation.
4. Confirm Drive Motor Functionality
If the drive motor isn’t functioning as it should, the pump may not build pressure. Here are a few things to check:
- Motor Speed and Torque: Ensure the motor is running at the speed and torque specified for your system. If either is too low, the pump won’t generate sufficient pressure.
- Alignment: Misalignment between the motor and pump can lead to binding of the drive shaft, reducing motor performance. Inspect and correct any alignment issues to restore proper function.
5. Inspect the Pump Coupling
A damaged or broken pump coupling can stop the pump from building pressure, even if the motor is working. This issue is often overlooked, especially if the pump is in a difficult-to-reach location. Inspect the coupling for signs of wear, breakage, or misalignment, and replace it if necessary.
6. Examine the Relief Valve Settings
The relief valve is designed to prevent excessive pressure in the hydraulic system. If the valve is stuck open or set too low, it can cause fluid to bypass the system, preventing pressure build-up. Check that the valve’s settings match your system’s specifications and adjust if necessary. If the valve is faulty, consider replacing it.
7. Check for Mechanical Damage
If none of the above steps resolve the issue, the problem may be mechanical damage inside the pump. Internal issues, such as worn bearings, a damaged pump shaft, or faulty components, can prevent the pump from building pressure. To diagnose this, disconnect the pump from the motor and try turning the pump shaft manually. If the shaft doesn’t rotate smoothly, it could indicate internal damage, which may require repair or replacement of the pump.
Conclusion
Troubleshooting a hydraulic pumps that are not building pressure requires a methodical approach. By working through this checklist, you can address common causes of pressure problems and potentially avoid unnecessary repairs or pump replacements. If you’ve followed these steps and the pump is still not building pressure, it might be time to reach out to a professional for further testing and repair services.
If you need expert hydraulic pump repairs or servicing, get in touch with us today.
Hydraulic Pump FAQs
- Why is my hydraulic pump not building pressure after startup?
- This could be due to air trapped in the pump or leaks in the suction line, which can disrupt fluid flow and stopping hydraulic pressure from building.
- How can I tell if my pump coupling is damaged?
- If the pump isn’t building pressure and everything else seems fine, inspect the coupling for visible damage, misalignment, or breakage.
- What happens if my relief valve is set too low?
- A relief valve set too low will cause fluid to bypass the system, preventing the pump from building adequate pressure.
- Can a reversed motor cause no pressure in my hydraulic system?
- Yes, if the motor runs in reverse, it will reverse fluid flow, stopping the hydraulic system from building pressure.
- How does misalignment affect the pump motor?
- Misalignment can cause the drive shaft to bind, reducing the motor’s performance and preventing pressure from building.
- When should I consider replacing the hydraulic pump?
- If all troubleshooting steps fail and you detect mechanical damage such as worn bearings or a damaged pump shaft, it may be time to replace the pump.
Hydraulic Component Services: Pumps We Support and Offer
At Hydraulic Component Services, we provide comprehensive support for a range of hydraulic pumps from leading manufacturers. We specialise in both repairs and servicing of these pumps to ensure your equipment remains reliable and efficient. Below are some of the hydraulic pump brands we support:
- Denison Hydraulic Pumps: Denison is known for its high-performance vane pumps, designed for heavy-duty industrial applications. We offer repairs and maintenance for all types of Denison hydraulic pumps, ensuring that your system performs optimally under demanding conditions.
- Parker Hydraulic Pumps: Parker is a globally recognised brand, offering a wide range of piston, vane, and gear pumps. Whether you have a Parker piston pump or vane pump in your system, we can provide expert repairs, replacements, and routine maintenance services to keep your hydraulic systems in top condition.
- Rexroth Bosch Group Hydraulic Pumps: Rexroth pumps are widely used in industrial and mobile applications due to their reliability and efficiency. We offer servicing and repairs for Rexroth hydraulic pumps, including their popular axial piston pumps, ensuring long-term performance and minimising downtime.
- Danfoss Hydraulic Pumps: Danfoss hydraulic pumps are known for their precision engineering and high efficiency, often found in mobile equipment and industrial machinery. We provide full support for Danfoss pumps, offering both repair services and preventive maintenance to extend the life of your pump and keep your operations running smoothly.
If you require any assistance with these or other hydraulic pump brands, contact us today for expert advice and support tailored to your needs.
