Your pool pump is the heart of the system. When it starts to fail, circulation drops, chemicals stop mixing, and the water can turn cloudy or green within days. The good news is that pumps almost always give warning signs first. Here are the seven most common ones, what each means, and how to tell a repair from a replacement.
1. It’s louder than it used to be
Screeching or grinding means worn motor bearings. A rattling, gravel sound is cavitation: the pump is starving for water because of a clogged basket, a closed valve or a suction-side air leak. Loud humming with no water movement means the motor has power but can’t spin (see sign 4).
2. Water on the equipment pad
A drip from the bottom of the motor is the classic sign of a failed shaft seal. It’s a cheap part, but once water gets past it, it runs into the bearings and a small repair becomes a motor replacement. Shut the pump off and get it looked at that week. Water around the lid or fittings is usually a cracked lid, hardened O-ring or loose union, all easy fixes.
3. Weak return flow
Empty both baskets, open every valve and clean the filter first. If flow is still weak, suspect a worn or clogged impeller or an air leak. Bubbles at the return jets are the giveaway for air; the pump lid O-ring, drain plugs and suction union are the usual sources.
4. It hums but won’t start, or trips the breaker
Most often a failed start capacitor, one of the cheapest pump repairs. Seized bearings or a jammed impeller are the other causes. Repeated breaker trips can mean the windings are shorting, which is the end of the motor. Don’t keep resetting it; each attempt heats the windings further.
5. It shuts off after a few minutes
That’s the thermal overload switch. The motor is overheating from blocked vents, failing bearings, low voltage or age. In summer heat a marginal motor will trip constantly.
6. Your electric bill jumped
A motor fighting bad bearings or a clogged line draws more current. It’s also the moment to consider a variable-speed pump, which runs at a fraction of the power most of the day and often pays for itself in two to three years.
7. It’s old
A pump motor typically lasts eight to twelve years. A seven-year-old pump that needs a $40 capacitor is worth fixing; a twelve-year-old single-speed pump that needs a motor is not. See how long pool equipment lasts for the full breakdown.
Repair or replace?
Repair when the part is cheap and the motor is under eight years old: capacitors, seals, O-rings, lids, impellers. Replace when the motor itself has failed on an older pump, when it’s needed two or more repairs in a year, or when the replacement would be a variable-speed model that lowers your bill. Utility rebates on variable-speed pumps come and go, so ask before you decide.
When to call
Baskets, valves, water level and vent debris are safe to check yourself. Anything involving the motor, the wiring or the shaft seal is a technician’s job; pool motors run on 230 volts next to water. If the pump is still noisy, leaking, weak or shutting down after the basics, our techs can diagnose it on the first visit and usually repair it on the spot. See our pool equipment repair page, and if the heater or filter is aging too, we’ll look at those while we’re there.
FAQ
Why is my pool pump humming but not running?
Usually a failed start capacitor, an inexpensive repair. Seized bearings or a jammed impeller are the other common causes. Turn it off at the breaker until it’s checked.
Is it safe to run a leaking pool pump?
Not for long. A shaft-seal leak sends water into the motor bearings and turns a small repair into a motor replacement.
How long should a pool pump last?
Eight to twelve years for the motor with regular maintenance. Heat, debris and running dry all shorten that.