4 Signs Your Pool Pump Capacitor Needs Replacing

The motor hums but doesn’t spin A humming sound means the motor is getting power but can’t start turning. The most common cause is a dead start capacitor.

The shaft spins freely by hand With power off, insert a screwdriver or Allen wrench into the hole at the back of the motor shaft and try turning it. If it spins freely but still hums when powered on, the capacitor is bad.

The impeller isn’t jammed Before blaming the capacitor, check that debris isn’t blocking the impeller. If it’s clear and the motor still hums, the capacitor is the likely culprit.

You’re comfortable with basic electrical work Capacitors cost $10–20 and are easy to swap with a YouTube tutorial. Discharge it first by shorting the terminals with a screwdriver. If you’re not comfortable, hire a pool professional—one mistake can ruin the whole pump.