Time: 30–45 minutes. Skill: comfortable laying an appliance on its back, removing a service panel, and tracing a wiring loom. Cost: under NZ$20 for the common 6µF/8µF film capacitors.
Diagnose first
The classic capacitor symptom: motor hums, drum doesn’t spin (or only spins when you nudge it). If the drum is locked solid or makes a grinding sound, it’s bearings — different repair. Capacitor symptoms appear suddenly: machine was fine yesterday, today it just hums.
What you’ll need
- The replacement capacitor — match µF (±5%). 450VAC is the standard run voltage.
- Phillips and flat screwdrivers. T20 Torx is handy for some Bosch/Siemens models.
- Insulated screwdriver for discharge.
- Phone for wiring photos.
- A second pair of hands if you’re tipping a top-loader on its back.
Steps
1. Unplug at the wall
Not just off — out of the socket. There’s no breaker for a single appliance and you don’t want to chance it.
2. Drain water from the hoses
Disconnect the cold-supply hose at the wall and let it drain. Pull the drain hose out of the standpipe and let it drain into a bucket. You’ll be tipping the machine to get at the bottom; you don’t want a litre of water in the drum lid.
3. Get to the motor
Front-loaders: usually a rear service panel held by 4–6 screws. Top-loaders: tip the machine on its back (don’t lay it on its front — control panel damage). The motor is the cylindrical lump attached to the drum belt (older) or directly to the drum (newer direct-drive).
4. Find the capacitor
Usually mounted near the motor on a bracket, with two wires going to the motor. Modern direct-drive machines have it integrated into a control board — if you can’t find a discrete capacitor, your machine is direct-drive and this guide doesn’t apply.
5. Discharge, photograph, swap
Same drill as any other capacitor: bridge the terminals with an insulated screwdriver for 5–10 seconds. Photograph the wiring. Pull the spades, swap the cap, re-fit the bracket, reconnect the spades the same way.
6. Reassemble and test
Service panel back on. Hoses back. Plug in. Run a short rinse-and-spin cycle. The motor should engage smoothly within a second of the cycle starting.
Common gotchas
- Direct-drive machines (most post-2015 LG / Samsung) don’t use a discrete capacitor — diagnosis is via the control board and it’s a service call.
- Belt-driven machines can throw the belt during a capacitor failure — check the belt while you’re in there.
- µF value on a washing-machine cap is typically printed on the side or inside the service door. If it’s worn off, count terminals: 2-wire is a run cap (small µF, 4–10µF). 3-wire is a dual-run.
If the motor still hums after a clean cap swap, the issue is bigger — bearings, brushes (on older universal motors), or control board. A motor service is usually cheaper than a new machine if the rest of the appliance is sound.