Quick answer
Drips and stiff levers are usually a cartridge, which is a cheap part and a short job. Leaks from the base of the spout are usually O-rings, also repairable. Corrosion at the base, a cracked body or a discontinued brand generally means replacement. A straight swap takes under an hour if the isolating valves work.
Key points
- Drip from the spout or a stiff lever: cartridge. Repairable.
- Water seeping around the base of the spout when you swivel it: O-rings. Repairable.
- Wet in the cupboard under the sink: check the flexi hoses before anything else.
- Standard NZ mixer tap hole is 35mm, which is why most replacements drop straight in.
- If the brand is discontinued or the body is corroded, replace rather than chase parts.
A kitchen tap is used more than anything else in the house and it is the fitting people put up with longest. Most of the faults that make a tap annoying are genuinely repairable with a part that costs very little, so it is worth knowing which is which before buying a new one.
Diagnosing it from the symptom
| Symptom | Likely cause | Repair or replace |
|---|---|---|
| Drips from the spout when off | Worn cartridge | Repair. Cartridge is the standard wear part |
| Lever has gone stiff or gritty | Cartridge, often scale | Repair |
| Water seeps from the base of the spout when you swing it | Spout O-rings | Repair, and worth doing with the cartridge |
| Water pooling in the cupboard | Flexi hose connection or the tail seal | Repair, but check the hoses closely. Failed flexis cause serious damage |
| Tap rocks or turns on the bench | Fixing nut loose underneath | Repair, tighten from below |
| Green or white corrosion at the base | Long-term seepage into the body | Replace |
| Spray head will not retract or leaks | Pull-out hose or weight | Repair if the part is available, otherwise replace |
| Part not available for the brand | Discontinued range | Replace |
The parts that are actually replaceable
On a typical single-lever mixer, the parts that come out are the lever and its grub screw, the decorative cap or shroud, the retaining nut, the cartridge, and the spout O-rings. Between them those cover most faults. The body itself and the internal waterways are not serviceable, which is why corrosion or a crack means a new tap.
Cartridges are not universal. They vary by brand and often by model within a brand, and the diameter matters. Taking the old cartridge to the merchant is more reliable than describing it.
How long a replacement takes
A straight swap on a bench-mounted mixer is usually well under an hour once you are set up. Isolate the supplies, disconnect the flexis, undo the fixing nut from below, lift the old tap out, drop the new one in and reconnect.
The things that make it take longer are almost always access and age. Isolating valves that will not turn mean shutting off the house supply. A fixing nut that has corroded onto the tail can take longer to remove than everything else combined. And on an undermount sink in a deep cabinet, simply getting a hand and a spanner into the space is the job.
Hole sizes and fitting a different tap
The standard tap hole in a New Zealand benchtop is 35mm, which is why most mixers are a direct swap. Where it gets awkward is going from a tap with a base plate to one without, because the new base may not cover marks or an oversized hole left by the old one. It is worth checking the base diameter of the new tap against what is there before ordering.
If you are moving from a two-tap set to a single mixer, you have two existing holes and will need either a mixer with a base plate that covers both or a benchtop repair, which on stone is not trivial.
Frequently asked questions
Is it worth repairing a kitchen tap?
Usually, if the fault is a drip, a stiff lever or seepage at the spout base. Those are cartridge and O-ring faults with cheap parts. Corrosion at the body or a discontinued brand is when replacing wins.
How long does it take to change a kitchen tap?
Under an hour for a straight swap where the isolating valves work. Seized valves or a corroded fixing nut can double or triple that.
What size is a standard mixer tap hole?
35mm in New Zealand benchtops, which is why most mixers drop straight into an existing hole. Check the new tap's base diameter if you are changing style.
Can I replace just the spout?
On many mixers yes, if the manufacturer still supplies the part for that model. On discontinued ranges it is often quicker and cheaper to replace the whole tap.
Why is water leaking into the cupboard under my sink?
Most often a flexi hose connection or the tap tail seal, sometimes the sink waste. Find the source before assuming it is the tap, and replace any flexi hoses of unknown age while you are there.