The hardest part of fixing a leaking faucet is getting to the job, but you shouldn’t put it off. Losing only one drop a second will waste a shameful amount of water. And the repairs after a year of leaking will be no easier than when the leak is first noticed.
The tools needed for faucet work are a large adjustable wrench, flat-blade screwdriver, Phillips screwdriver and pliers. If the faucet you are working on is a tub-shower faucet, you may need a set of special socket wrenches that cost about $10. These reach behind the wall to remove the packing nuts so you can remove the valve stems. With the stem out, tub-shower washer service proceeds as with smaller faucets.
Here are the basic steps:
First, turn off the water supply. If you’re fixing just one side, hot or cold, of a dual-handle faucet and the fixture has handy shutoff valves beneath it, you need to turn off only the side to be worked on. Lacking under-fixture shutoffs, you’ll have to turn off the branch water supplies or the main house supply.
Remove the faucet handle. Do this by loosening the Phillips-head screw that holds it to the stem. Sometimes this screw is located beneath a decorative trim cap in the center of the handle. The cap either unscrews or can be snapped off by prying it with a putty knife. Handles lift or are pried off of the upper end of the stem.
Examine faucet parts for signs of bad corrosion. You may want to consider replacing them. Also, it may be advisable to replace the entire faucet assembly.
Remove the packing nut, which is directly below the handle. This will reveal the stem and any old packing around the stem. On the other end of the stem, you may find a rubber O-ring, and just beyond, the seat washer secured to the end of the stem with a washer screw. Then you will see the packing-nut washer and the faucet seat.
Remove any old packing from around the stem and examine the stem. If it shows areas that are badly rusted or corroded, replace it if possible.
Check the seat washer, which is probably the source of the leak or the drip. See if it has a flattened appearance or a groove. It may also be ragged or cracked because it has become brittle with old age.
Replace this washer, whether it appears to be in good shape or not. It is secured with a screw. If the screw is rusty, replace it with a brass screw.
It is not easy to tell much about a faucet seat by looking at it. For best results and to avoid having to repeat this whole procedure soon, replace it too. Be sure to get one of the same size and shape as the old one. Some are flat and some are beveled, and there are about three or four common sizes.
Always take small parts to be replaced with you when you go to the plumbing supply or hardware store. While you are at the store, buy a small pack of flexible packing if you had to remove the old packing from around the stem. This is simply wound around the stem for about four or five turns just above the threads.