How to Repair a Single Handle Kitchen Faucet

Faucet repair with a wrench.
What You'll Need
Pocket knife
Allen wrench
Oil lubricant
Slip joint pliers
Needle-nose pliers
Plumber’s grease
O-rings or cartridge assembly

It's fairly common for a single handle kitchen faucet to spring a leak at some point in its life, especially considering all the use such a device gets. Although most leaks are easy to fix, if the faucet isn't dealt with immediately even the smallest of leaks can cost a lot of money in the long run. Whether water is seeping through the base or dripping from the spout, the repair can be accomplished in an afternoon by following these simple steps.

Step 1 - Turn Off the Water Supply

Before you grab the wrench and go to work on the leaking faucet, you'll need to turn off the water supply. Locate the water valves, which are typically right under the sink, and tighten them to turn off the water. If your sink doesn’t have any valves underneath, then you’ll need to turn off the main water line to your house.

Step 2 - Drain the Water in the Lines

After the water has been successfully turned off, you’ll need to drain any excess water in the lines. To accomplish this, simply turn on the faucet and wait for the dripping to stop. Once all the water has been drained, place a towel in the sink to make sure any loose parts don’t accidentally fall in the drain as you're working.

Step 3 - Remove the Handle

With the faucet now ready for repair, you’ll need to first remove the handle. This is done by removing the decorative plastic cap located above the base of the faucet with a small pocket knife. This cap conceals a screw that keeps the handle locked down in place. Once the screw is exposed, use the appropriate screwdriver or allen wrench to remove it. If the screw won’t budge, try adding some lubricant and be careful not to strip it out. Once it's removed, jiggle the handle and it should slide off with little force.

Step 4 - Remove the Bonnet

The next thing to do is to remove the bonnet in order to access the cartridge assembly. To do this, use a pair of slip joint pliers to unscrew the bonnet. Once the bonnet has been unscrewed, use your needle-nose pliers to gently slide the retainer clip out of the faucet base. As you remove these pieces, set them aside and arrange them in the same orientation as they were on the bonnet. This will help you remember how they were organized, which will come in handy when you reinstall the bonnet.

Step 5 - Determine the Leak's Source: O-Ring or Cartridge?

Before you move forward, you’ll need to determine where the leak is coming from. If the leak is coming from the handle’s base, then the problem is likely some worn O-rings on the cartridge that need to be replaced. Remove the rings with a knife, and coat the new ones with some heat-proof plumber’s grease. However, if the leak is coming from the spout, then an entirely new cartridge assembly needs to be installed.

Step 6 - Remove the Cartridge

To remove the old cartridge, simply use your pliers at the base of the cartridge and pull up with a generous amount of strength, making sure not to pull it from side to side. You may have to pull hard because the O-rings can generate a good amount of suction and resistance. The key here is to avoid damaging the rest of the faucet, as you’ll need it fully intact when you install the new cartridge.

Step 7 - Install the New Cartridge

With the old cartridge removed, it's time to put in the new one. Make sure that when you install the new cartridge into place, you correctly place it in the exact same position as the old one. This will ensure that the hot and cold water holes are not confused.

Step 8 - Reinstall the Handle

With the new cartridge correctly in place, simply fit the old retainer clip back onto the right slot. Reference how they were positioned when you initially took them off to ensure a tight fit. Then place the bonnet over the cartridge, screw it down with your slip joint pliers, and reinstall the handle. With everything back together and the handle screwed on, turn on the water valves to the sink and check to make sure the leak has been fixed. Once you're certain everything is working properly, reinstall the decorative plastic cap and the faucet is ready for use.