A dripping faucet can waste water, drive up your utility bill, and become downright annoying. If you’re dealing with a Delta single handle bathroom faucet that refuses to stop leaking, this DIY guide walks you through the entire repair process or watch our full repair video above.
Diagnose the Leak
The first step is determining the source:
- Is it dripping slowly from the spout?
- Do you notice water pooling around the base or handle?
- Does the faucet spray when turned on?
In the video, I highlight a dripping faucet from the spout.This issue is often caused by worn-out internal seals or cartridges or in our case seats and springs.
Gather the Right Tools and Parts
To complete this repair, you'll need:
- Milwaukee adjustable wrench
- Screwdrivers (flat and Phillips)
- Allen wrench or hex key (we recommend this Delta Set Screw & Allen Wrench, if you are missing the set screw)
- Replacement cartridge - this is specific to the Delta models, we used Delta RP4993 seats and springs, you may need something different depending on the model of the faucet you have.See all our Delta replacement cartridge options here.
- Plumber’s grease
Make sure you identify the cartridge model used by the faucet, ensuring you replace it correctly. If you have any questions, feel free to reach out.
Disassemble the Faucet
Step-by-step disassembly:
1. Turn off the water supply—very important! Double check by lifting the handle.
2. Use the Allen key to remove the faucet handle by undoing the set screw. I used a 1/8" Allen key in the video.
3. Gently lift off the handle and inner bonnet.
4. Use the wrench to unscrew the bonnet or retaining nut/clip securing the cartridge.
5. Carefully extract the old cartridge.
Emphasize caution—don’t force parts or damage adjoining metal components.
Inspect and Clean Internal Components
With the cartridge removed:
- Examine it for cracks or mineral buildup. Usually, it's the seats and springs that are worn out. But this will vary.
- Look at O-rings and seals—if they seem brittle or flattened, they definitely need replacing.
- Clean inside the faucet body to remove debris or scale buildup.
A clean base helps ensure a proper seal and lasting repair.
Install the New Cartridge and Seals
- Apply a thin coat of plumber’s grease to new seals and O-rings.
- Insert the new cartridge into the faucet body, ensuring it aligns correctly with the notches.
- Tighten the retaining nut or clip as shown in the video.
- Reattach the bonnet and handle, making sure everything fits snugly.
Reassemble and Test
- Turn the water supply back on.
- Move the handle around to test for leaks.
- Keep it open for a few seconds to fill the lines and then check for drips.
The Lasting Value of Quality: Repair Over Replace
Investing in a quality faucet, like a Delta, means you're choosing durability over disposability. A well-made fixture isn't just about avoiding annoyance from a drip; it's designed for easy repair.
This means that while your initial investment might be a bit more, you'll save significantly in the long run. Instead of constantly replacing cheaper alternatives, you can maintain and repair your quality faucet for years. This guide shows you how simple it is to fix a leak, proving that repairing is a smart, sustainable choice that maximizes your investment and saves you money.
