How to Fix a Leaky Faucet: Basic Steps

A bathroom Faucet

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A leaky faucet—one that drips from the spout and can't be shut off fully—is a nuisance that you will probably face at some point. Even slow drips lead to higher water bills, wasted water, and the potential for water damage. On top of that, the sound of incessant dripping is enough to push anyone over the edge. Fortunately, fixing a leaky faucet is a relatively simple task and one that you can complete without having to call in the plumber.

Why Faucets Leak

All faucets work by controlling the flow of water through the use of an inner stem or cartridge with rubber or neoprene washers or seals that open and close against water inlet ports inside the faucet body. When these seals don't properly fit, it allows a small amount of water to continue up to the faucet spout, where it creates that maddening and wasteful drip, drip, drip. The failure to seal can be caused by corrosion, by foreign material inside the faucet body, or (most often) by washers or seals that have lost their resiliency and are failing to seal properly.

There are some problems that can occur with any faucet type:

  • Mineral (scale) buildup on the inner parts can cause any faucet to leak, since this mineral buildup interferes with the faucet's ability to seal the water inlets. Here, you may be able to clean away scale and restore the faucet to good operating condition.
  • Corrosion of parts within the body of the faucet. This can deform the water inlet ports to such a degree that the washers or seals on the faucet stem or cartridge can no longer seal properly and stop the flow of water. In this case, the practical solution is the replace the entire faucet, since repairs—even if they are possible—may not be cost-effective
  • Leaking around the base of the spout is usually caused by worn O-rings around the body of the faucet underneath the spout assembly. This can occur with either cartridge faucets or traditional compression faucets.

Other problems, however, are particular to the style of faucet:

  • Traditional compression faucets usually drip from the spout when a stem washer becomes worn out, dry, and cracked. The answer here is usually to simply replace the stem washer.
  • A cartridge faucet, whether a single-handle and double-handle model, usually leaks because the rubber or neoprene seals along the cartridge become worn. These seals can sometimes be replaced, but often the easiest solution is to replace the entire cartridge.

Pinpointing the cause for a dripping faucet may not become clear until you disassemble the faucet and inspect the parts.

Tools and Supplies You Will Need

To shorten the amount of time it takes to complete the project, be sure to gather all of the tools and materials required before you start. The materials you may need to repair a leaky faucet include:

  • Adjustable wrench
  • Channel-lock pliers
  • Allen wrenches
  • Flathead screwdriver
  • Phillips-head screwdriver
  • Spray penetrating oil (if needed)
  • White vinegar
  • Scouring pad
  • Washers and seals
  • Replacement faucet cartridge (if needed)

Instructions

  1. Shut Off the Water

    Always turn the water off before beginning a leaky faucet repair. Failure to do so can lead to an instant flood when you begin disassembling the faucet.

    Locate the fixture shutoff valves below the sink and turn the handles clockwise to shut off the flow of water to the fixture. If the faucet has no fixture shutoff valves, you can turn off the main water supply for the entire house.

    Turn on the faucet to verify that the water is shut off and to relieve pressure from the lines. Cover the drain with a stopper or cloth to avoid losing any small parts down the drain.

  2. Remove the Faucet Handles

    The process for removing the handles on a faucet depends on the faucet. On standard faucets, you can often use a flathead screwdriver to remove decorative caps on top of the handle, which will reveal handle screws. Unscrew these, then pull the handles then. Some single-handle faucets are held in place with a hex setscrew set into the handle; loosen this screw and the handle should lift off with an upward pull. If the screws or other handle parts are corroded or difficult to remove, then use spray oil to lubricate and loosen the parts.

    Set the parts aside in order as you disassemble the faucet. and make a note as to where they go and how to reinstall them.

  3. Remove Valve Stem or Cartridge

    With the faucet handle removed, the inner valve stem or cartridge will be revealed. This part needs to be extracted from the body of the faucet. The technique for extraction will vary, depending on the style of the faucet and shape of the parts.

    Some compression faucets have a brass valve stem that unscrews from the valve body. Cartridge faucets, on the other hand, generally use a plastic or brass cartridge assembly that pulls straight out of the faucet body. Sometimes there is a collar nut or brass retaining clip that needs to be removed to free the cartridge. Refer to the faucet manual, or look up online directions, for instructions on how your particular cartridge should be removed.

  4. Inspect the Faucet Parts

    Carefully inspect the parts of the stem or cartridge you have just removed. Depending on the faucet style, this can include traditional rubber washers, rubber O-rings, and ring-shaped rubber seals. On single-handle faucets, there may also be large O-rings around the body of the faucet, which serve to seal the spout and keep water from leaking around the base of the faucet, as well as springs and rubber seals located down inside the brass body of the valve. Make sure to look carefully and inspect all parts that can be removed.

  5. Replace Necessary Parts

    If any parts appear old or damaged, replace them at this time. It is often a good idea to replace all the removable parts, performing a total faucet tuneup. Many manufacturers sell kits that include all the parts necessary to tune up a particular faucet model. For cartridge faucets, you can buy kits that include replacement seals only, or you can opt to replace the entire cartridge. The easiest way to get the correct replacement parts is to take the old parts to the hardware store and ask for exact duplicates.

  6. Clean the Valves

    With all of the parts removed from the faucet, you can inspect the valve body—the brass assembly from which the stem or cartridge was removed. You may find these brass parts roughened or pitted with a buildup of mineral scale. Pour white vinegar over the valve seat and let it soak for several minutes. Then use a nylon scrub pad to clean the surfaces. The goal is to return the brass to a shiny, smooth condition. Remove the stopper from the drain and pour clean water over the valves to rinse away any dirt and debris.

    If you are keeping the old valve stem or cartridge, also inspect these parts and clean them with vinegar and a scrub pad.

  7. Reassemble the Faucet

Carefully put the faucet back together, reversing the order used when you took the faucet apart. Turn the water supply back on and inspect the faucet for leaks.

Know When to Replace the Faucet

As with anything else, faucets deteriorate with age and need to be replaced sooner or later. If the faucet you are working with is old, then it might be time to replace it with a new one. Most faucets have a lifespan of about 10 years before they require major repairs or replacement. Compression faucets are growing increasingly obsolete, and you are well-advised to replace them with modern cartridge faucets rather than attempt repairs. Consider replacing the faucet if you notice any of the following:

  • Leaks from multiple areas
  • Extensive corrosion to inner parts
  • Hard-to-find replacement
  • Visible damage