Don't guess. Test. Know exactly what your hydraulic pump is doing.
Our in-house HP/QP test bench is one of the few facilities of its kind in New Zealand. We use it to test components after every rebuild. Nothing goes on to our test rig before being torn down and checked first.
When should you get your pump checked?
Hydraulic faults don't always announce themselves clearly. These are the signs that warrant a strip and assess before you make any decisions about repair or replacement:
- Slow or sluggish actuator/cylinder movement, or loss of speed under load.
- Reduced system pressure or inability to reach rated pressure.
- Loss of power — the machine bogs down or stalls when working hard.
- Erratic, jerky, or inconsistent operation.
- Excessive or unusual noise (whining, growling, knocking).
- Cavitation noise (rattling/"marbles" sound), suggesting the pump isn't getting enough fluid.
- Aeration noise (higher-pitched, irregular) from air in the system.
- Increased vibration.
- Overheating hydraulic fluid or an unusually hot pump case.
- Heat concentrated at the pump relative to the rest of the system.
- Milky or foamy fluid (air or water contamination).
- Metal particles in the fluid or on filters/magnetic plugs (internal wear).
- Discoloured or burnt-smelling oil.
- Rapid filter clogging.
- External leaks at the shaft seal, case drain, or fittings.
- High case drain flow — a strong indicator of internal wear/bypass.
What our test rig measures
Our purpose-built HP/QP test bench is designed specifically for hydraulic pump and motor testing, here's what we assess:
- Pressure (HP) performance - We measure the hydraulic pressure output of your pump and compare it against the manufacturer's rated specification for that model where possible.
- Flow (QP) performance - Flow rate testing identifies whether your pump is delivering the volume of fluid required to operate your machine correctly at rated conditions.
- Where possible, we reset the pump to manufacturer specifications on the bench.
What happens next
Where possible, we are comparing how your component performed against manufacturer specification or the specifications provided by you for your application.
If the manufacturers specifications aren’t available then we test based on the theoretical displacement of the pump and check to make sure it is responding to inputs to de-stroke or stroke the pump according to its control type.
Our HP/QP test bench is based at FPD's workshop, 205 Ellis Street, Frankton, Hamilton. Components can be dropped off, sent in from anywhere in New Zealand, or tested as part of an existing rebuild job.
Not sure what's wrong with your pump? Get it tested and know for certain.
