Pump troubleshooting
My pump has become noisy
Pumps make some noise, but a change in the noise is worth listening to. The kind of sound often points straight to the cause.
Pumps make some noise, but a change in the noise is worth listening to.
What the sound is telling you
| The sound | Usually means | What to do |
|---|---|---|
| Grinding or rumbling that gets worse over time | Worn motor bearings | A service or a replacement motor |
| Gravel or marbles in a can while running | Cavitation: the pump is struggling to draw water | Check the inlet, valves, filter and suction line size |
| A rattle or buzz | Loose mounting or pipes | Bolt it down firmly; check anti-vibration mounts |
| A loud hum with little or no water moving | An electrical or start fault | Switch it off; see slow to start |
What to check
- Confirm it’s the pump and not the pipes (see the water hammer guide).
- Check the pump is bolted down firmly on a solid base, with any anti-vibration mounts in place.
- For a gravelly cavitation sound, check the suction side. A blocked inlet, a partly closed valve, a clogged filter, or too small a suction line makes the pump starve.
- Grinding bearings generally mean the motor needs a service or replacement.
When it’s the bearings
Bearings are a wear item. A pump that has run for years and developed a steady grinding or rumbling that rises with speed is usually telling you the bearings are on the way out. On many pumps that’s a service job; on others it’s the point where replacing the pump makes more sense than repairing it.
Common questions
Can I keep using a noisy pump?
A minor new noise, keep an eye on it. A loud grinding, or a hot pump that hums but won’t move water, stop using it and investigate, as you risk further damage.