A faucet that drips once every few seconds can waste a surprising amount of water, but the real problem is usually not the drip itself. To repair a dripping valve correctly, you need to identify where water is escaping and which internal part is actually worn. Replacing a handle or buying a generic cartridge because it looks close can turn a simple repair into a second trip to the supply counter.
Most fixture repairs come down to a worn sealing surface, a damaged stem, a failing cartridge, or a loose packing nut. The correct fix depends on the valve design, the fixture manufacturer, and whether the water is leaking from the spout, around the handle, or from a shutoff valve under the sink.
Repair a Dripping Valve: Find the Leak First
Start with the water path. If water drips from the faucet spout after the handle is turned off, the valve is not fully sealing inside the fixture. On a two-handle faucet, that usually points to the hot or cold stem assembly, its rubber washer, seat, or ceramic cartridge. On a single-handle faucet, the cartridge, ball assembly, or inlet seals are the likely source.
If water appears around the handle only while the faucet is running, inspect the packing nut and stem seals. A packing nut that has loosened slightly may stop the leak with careful tightening. Do not overtighten it. Excess pressure can make the handle difficult to turn or damage older parts.
Water coming from a shutoff valve below the sink is a different repair. A leak around the stem may respond to a small adjustment of the packing nut. A leak from the outlet, inlet, or valve body may mean the compression connection, supply line, or the shutoff valve itself needs replacement. Do not assume a faucet repair kit will solve a leaking angle stop.
Before taking anything apart, dry the fixture completely and watch where the first drop forms. This saves time and prevents ordering the wrong service part.
Shut Off Water and Open the Fixture Carefully
Turn off the local stops under the sink when they operate properly. For a tub or shower valve, you may need to use the home’s main water shutoff or dedicated service stops behind an access panel. Open the faucet after shutting off water to relieve pressure and confirm that flow has stopped.
Cover the drain before removing screws, handle adapters, or retaining clips. Small clips and handle screws disappear quickly. Take clear photos at each stage, especially before removing a stem or cartridge. The position of a cartridge, the shape of its retaining clip, and the broach at the top of a stem are useful identification details.
Remove the handle cap, set screw, and handle. Depending on the fixture, you may find a bonnet nut, retaining nut, threaded sleeve, or horseshoe-style clip holding the working part in place. Use the correct wrench or socket where possible. Decorative sleeves and plastic retainers crack easily when gripped with pliers.
Older fixtures deserve extra patience. Mineral buildup can lock a stem or cartridge into the valve body. Apply controlled force, not brute force. If a cartridge will not come out, confirm that every retaining part has been removed before pulling. Breaking a cartridge inside a valve body can turn a routine repair into a much larger job.
Identify the Part Before You Order It
The internal part is the important part, not the handle finish. Many faucets that look alike use completely different stems, cartridges, and diverters. Manufacturer names such as American Standard, Delta, Price Pfister, Crane, and Wolverine Brass each have legacy designs that may be decades old and no longer resemble current production fixtures.
Look for a manufacturer mark on the faucet body, escutcheon, handle, or old component. Then compare the removed part using details that do not change: overall length, thread location, spline or broach count, stem direction, number of O-rings, seal arrangement, and the shape of the base.
For a compression-style stem, inspect the rubber washer at the bottom and the brass seat inside the valve body. A flattened, split, or hardened washer will not seal. If the seat is pitted, rough, or scored, installing a new washer alone may not last. The seat may need to be replaced or resurfaced, depending on the fixture design.
For a cartridge faucet, inspect the cartridge body and the valve housing. Torn O-rings, cracked plastic, worn seals, and mineral deposits are common problems. A cartridge can also look acceptable while its internal ceramic discs or seals have failed. When the part has a known matching replacement, replacing the complete cartridge is generally more dependable than trying to rebuild it with improvised seals.
Do not use a universal part unless the fixture manufacturer specifically supports it. Universal repair kits are useful for certain common compression faucets, but they are not a reliable answer for proprietary cartridges, diverters, shower stems, or older specialty fixtures. Exact compatibility matters more than a low initial price.
Replace Seals, Stems, and Cartridges Correctly
Clean the valve body before installing the replacement part. Remove loose mineral deposits and old pieces of rubber, but do not scratch sealing surfaces inside the body. A soft brush, cloth, and appropriate non-damaging cleaner are usually enough. Flush debris carefully only after the internal components are out and the water can be controlled.
Use plumber’s silicone grease only where the manufacturer calls for it, typically on cartridge O-rings and certain moving seals. Petroleum grease can damage some rubber compounds. Do not coat ceramic sealing faces, washer seats, or threads with excessive grease.
Install the part in the same orientation as the original. This is especially important with single-handle cartridges and pressure-balance shower cartridges. Reversing a cartridge can cause hot and cold water to operate backward, and incorrect alignment can prevent the retaining clip from seating.
Reassemble the fixture hand-tight first, then tighten retaining and bonnet nuts only enough to secure the component and seal the assembly. Over-tightening is a common cause of cracked plastic cartridge nuts, stripped threads, and stiff handles. Reinstall the handle after the internal repair is complete.
Test the Repair Before You Call It Finished
Turn the water supply on slowly. Keep the handle in the off position and watch around the bonnet, packing area, supply connections, and valve body. Then run both hot and cold water and operate the handle through its full range.
Check the spout after shutting the faucet off. A few leftover drops may come from water trapped in the spout or aerator. Continued dripping after a minute or two means the valve is still not sealing. If the fixture now leaks around the handle, the packing nut may need a minor adjustment or an O-ring may be out of position.
A repaired shower valve should also be checked with water flowing at normal house pressure. Some leaks only show up when the cartridge is under pressure. Confirm temperature operation and look behind the trim plate if there is any sign of water escaping from the valve body.
When a Repair Part Is Not Enough
A valve body with cracked brass, severely damaged threads, or a corroded cartridge chamber may not be worth rebuilding. The same is true when a shower valve is inaccessible and the repair would risk damage inside a finished wall. Replacement can be the practical choice, but it should not be the automatic choice just because a fixture is old.
For older fixtures, a correct stem, cartridge, diverter, handle adapter, or rebuild kit can keep an existing faucet operating for years without replacing the whole assembly. If the part cannot be identified from a number, clear photos of the removed component, the fixture, and the handle connection usually provide the details needed to narrow it down. Bare Bones Plumbing Supply specializes in the repair parts that keep these fixtures in service.
The best repair starts before you order anything: isolate the exact leak, remove the old part without damaging it, and match the replacement by its working dimensions and design. That approach stops the drip and keeps a small valve problem from becoming a fixture replacement.