Seven Signs that a Hydraulic Pump Needs Repairs or Replacement
If your hydraulic pump is showing any of the following signs, it may be in need of repair or replacement:
- Unusual noises
- Overheating hydraulic fluid
- Reduced pump performance
- Rapid part wear
- External leaks
- Cloudy hydraulic fluid
- Inconsistent or delayed maintenance
In many cases, these problems will appear before the pump experiences complete failure. As soon as they emerge, it’s recommended that equipment operators schedule a prompt, expert inspection for their hydraulic pumps. This will help your organization prolong equipment life, avoid costly downtime, and maximize the return on your pump investment.
Here Are 7 Signs That Your Hydraulic Pump May Need Repairs or Replacement
1) The Hydraulic Pump is Making New and Unusual Noises
During operation, hydraulic pumps output a consistent sound that operators quickly get used to. If these sounds change, it could be a sign that there’s a problem, such as:
- Aeration
- Cavitation
- Excessive mechanical wear
- Sticking valves
- Failing seals or bearings
Some of these problems may indicate imminent failure. Cavitation, for example, will cause rapid wear to internal parts, resulting in sediment formation that damages downstream components. Cavitation is characterized by a whining sound that may turn into a growl or rattle in severe cases.
Banging, knocking, or slamming noises should also be investigated. These may also indicate aeration or cavitation, or a malfunctioning valve. If the sounds are coming from a hydraulic cylinder, it may be caused by a bent rod that’s binding.
2) The Pump's Hydraulic Fluid is Overheating
Hydraulic fluid is temperature-rated for ideal operating conditions. If temperatures climb too high, it will reduce the fluid’s viscosity (thin it out) and reduce its performance. Specifically, reduced-viscosity fluid will not flow as efficiently and will provide poor lubrication.
If the hydraulic pump’s fluid is overheating, it could be due to an over-pressured hydraulic pump (which increases friction). It could also be due to fluid contamination, as sediment will clog filters, valves and hydraulic lines, obstructing flow. Fluid overheating may also be caused by a blocked heat exchanger.
3) The Hydraulic Pump’s Performance Has Slowed (or Stopped)
For many pumps, the first sign of failure is loss of flow. If the pump cannot deliver rated flow or torque, or if the pump operates slowly, there is something wrong with the system.
Loss of operating flow, pressure, or torque may be caused by:
- Leaks, either internal or external
- Hydraulic fluid overheating
- Low or contaminated fluid
- Improperly calibrated valves (the relief valve, in particular)
- Aeration
- Mechanical damage to internal components
Several of these issues will worsen with time if they are not addressed, so any drop in pump efficiency should be investigated.
4) The Hydraulic Pump's Components Require Frequent Replacement
If your hydraulic system seems to cycle through certain components more rapidly, it could be due to the following:
- A misaligned or bent actuator
- Overheating hydraulic fluid
- Fluid contamination
- Cavitation or aeration
- Improper system design or configuration
Unsurprisingly, load-bearing parts tend to fail more often. In hydraulic systems, seals are a frequent failure point, especially in hydraulic cylinders. Seal failures are much more common when fluid is contaminated or overheating. When a seal fails, it results in leaks and loss of power.
5) There are Visible Leaks on the Hydraulic Pump Body or Fittings
If leaks emerge inside of the hydraulic pump or system, you’ll first notice a drop in flow or actuator speed. However, some leaks are more obvious.
Visible leaks will also cause a drop in flow and work efficiency, and they tend to emerge around the following components:
- The pump’s body and piping
- Pump couplers or connectors
- Hydraulic hoses and hose connectors
- Hydraulic cylinders
Failed seals are the number one cause of leaks, but they can also be caused by failed couplings or tears in hydraulic hoses. However, it’s not always clear where external leaks are originating as fluid may flow from where it exits the system.
This can make it difficult to isolate external leaks, but the sooner they are caught, the less damage they will do. Following every job, it’s important for operators to give the hydraulic system a visual inspection and verify that fluid isn’t pooling anywhere around it. This is also a good time to wipe down the equipment to keep contaminants from entering the system.
6) There is Water or Sediment Contamination in the Hydraulic Pump's Fluid
Contamination is responsible for the majority of hydraulic pump failures. If it’s present in your system, it may cause:
- Rapid component wear
- Overheating
- Flow problems
- Aeration and cavitation
- Total pump failure
Avoiding contamination should be a top priority for your operators. To keep your system contaminant-free, the following maintenance tasks are recommended:
- Sample hydraulic fluid regularly. Take multiple samples and check for any signs of sediment or cloudiness. If fluid is cloudy, it’s likely contaminated by water.
- Wipe down hoses, connections, the hydraulic pump body, and cylinder bodies after use.
- Inspect any unusual sounds, overheating, or loss of power immediately as these are tell-tale signs of contamination.
- Only use hydraulic fluid that’s rated for the pump and replace at recommended intervals.
- Inspect and replace seals as soon as wear or damage is present.
- Verify that the breather cap and suction filter are clean.
- Observe proper storage and maintenance procedures. Hydraulic pumps should be stored in a clean, dry place between jobs.
7) The Hydraulic Pump Hasn't Received Regular Maintenance
The best way to avoid costly hydraulic pump failures is with preventative maintenance. Most manufacturers recommend a round of service every 10,000 hours.
If your hydraulic pumps and equipment haven’t been put on a regular maintenance schedule, you could be looking at costly repairs or replacement soon. Consider getting those hydraulic pumps inspected by an expert hydraulic equipment expert, and also consider implementing an equipment tracking system.
An equipment tracking system will ensure your hydraulic pumps are serviced on time and that any performance issues are noted and addressed before they cause downtime.
If it has been a while since your hydraulic pumps were inspected, or if your hydraulic systems are showing signs of wear, damage, or inefficiency, it’s time to bring in the experts.
A hydraulic power technician can perform a full system inspection of all your hydraulic pumps, cylinders, and other components. This includes breaking each piece of equipment down, inspecting every part and diagnosing any issues.
If your crew doesn’t have the time or expertise to keep up with hydraulic pump maintenance, consider partnering with a hydraulic equipment technician to ensure your hydraulic pumps remain in reliable working order.