Quick answer
To fix a leaky sink faucet, turn off the water supply, disassemble the faucet, inspect for worn washers or O-rings, and replace them. Reassemble and test for leaks.
Confirm the symptom
- Water dripping from the faucet when off
- Low water pressure
- Faucet handle is loose or wobbly
- Water leaking at the base of the faucet
- Unusual noise when faucet is on
Tools and prep
- Adjustable wrench
- Screwdrivers (flathead and Phillips)
- Plumber's putty or silicone sealant
- Replacement washers, O-rings, or cartridge
- Bucket or towel to catch water
- Turn off water supply under sink
- Work in a well-lit area
Step-by-step troubleshooting
- Turn Off Water SupplyDo: Locate and turn off the shut-off valves under the sink.Observe: Water stops flowing from the faucet.Means: Water supply is safely off.Next: Disassemble the Faucet
- Disassemble the FaucetDo: Use a screwdriver to remove the handle and expose the internal components.Observe: Access to the stem, cartridge, or O-rings is clear.Means: You can now inspect internal parts.Next: Inspect for Damage
- Inspect for DamageDo: Check for worn washers, cracked O-rings, or a damaged cartridge.Observe: Visible signs of wear or damage.Means: Identify the part causing the issue.Next: Replace Faulty Parts
- Replace Faulty PartsDo: Install new washers, O-rings, or a cartridge as needed.Observe: Parts fit snugly and securely.Means: Leak or pressure issue should be resolved.Next: Reassemble the Faucet
- Reassemble the FaucetDo: Put the faucet back together in the reverse order of disassembly.Observe: Faucet is fully reassembled and handle moves smoothly.Means: Faucet is ready for testing.Next: Test the Faucet
- Test the FaucetDo: Turn the water supply back on and check for leaks or pressure issues.Observe: No leaks and water flows properly.Means: Issue is resolved.Next: Done
Common causes
| Cause | Likelihood | Difficulty | Part often needed |
|---|---|---|---|
| Worn Washer Over time, the rubber washer inside the faucet wears out, causing leaks. | Common | Easy | Washer |
| Damaged O-Ring The O-ring can crack or wear, leading to leaks at the base or handle. | Common | Easy | O-Ring |
| Faulty Cartridge A worn or damaged cartridge can cause leaks or poor water flow. | Sometimes | Medium | Cartridge |
| Loose Handle A loose handle can cause the faucet to leak or not shut off properly. | Sometimes | Easy | Handle Screws |
| Clogged Aerator Mineral buildup in the aerator can reduce water pressure. | Sometimes | Easy | Aerator |
| Corroded Valve Seat Corrosion on the valve seat can prevent a proper seal. | Rare | Medium | Valve Seat |
| Worn-Out Gasket A deteriorated gasket can cause leaks at the base of the faucet. | Rare | Easy | Gasket |
Parts matching
Match your faucet issue with the right part:
- Leak from spout: Washer or cartridge
- Drip from handle: O-ring
- Low pressure: Aerator or cartridge
- Leak at base: Gasket or O-ring
- Loose handle: Handle screws
Take the old part to the hardware store for an exact match.
When to call a professional
- Faucet is old (pre-1980s) and parts are no longer available
- You can't turn off the water supply easily
- The leak continues after replacing parts
- You're dealing with a whole-house water pressure issue
- You're uncomfortable working under the sink
FAQ
How do I know if my faucet needs a new cartridge?
If the faucet leaks continuously or has poor water flow after replacing washers and O-rings, the cartridge is likely the issue.
Can I fix a leaky faucet without turning off the main water supply?
Always turn off the shut-off valves under the sink first. If they don't work, you may need to turn off the main water supply to avoid flooding.
Why is my faucet making a clicking noise?
A clicking noise often indicates a worn washer or loose handle. Check and replace these parts as needed.
How often should I replace faucet parts?
Inspect and replace washers and O-rings every 5–10 years, depending on usage and water quality.
What if my faucet still leaks after replacing parts?
Double-check the installation for proper alignment and tightness. If the leak continues, the valve seat may be corroded and need replacement.