Replacing faucet washers is an easy task that can make an old faucet work like new again. First you need to know if your faucet has washers, many of today’s faucets are washerless designs. A faucet that has washers will often turn several times to open or close and will not have a hard stop where it turns off. To repair a faucet that is dripping and uses washers there is more to the job than just replacing the washer. Often when a faucet starts dripping the water will erode a rough area or, groove in the seat the washer presses against to stop the water. If the seat is rough the new washer will not seal and the faucet will continue to drip or, the rough seat will tear the new faucet washer apart. When I repair a faucet I repair both sides together so I don’t have to do it all over again on the other side in a few weeks. For a successful faucet repair there is no substitute for doing the complete job.
Replacing the faucet washer will require a few tools to complete the job, you will need a screwdriver, and adjustable wrench for starters. In addition to those you may need a faucet handle puller and you will need a seat wrench. For bathtub faucets you may need a faucet socket set to reach inside the wall to remove the stem. The first step is to shut off the stop valves under the sink and make sure the water is turned off by turning the faucet to the on positions and making sure that water is off. On bathtubs in most cases you will need to turn off the water to the whole house. Remove the screw from the handle then try pulling the handle off, sometimes a rocking motion helps. If the handle does not pull off easily you will need a faucet handle puller to take the handle off. Once the handle is removed in many cases you will see two nuts on the stem, the smaller or, first nut is a packing nut, which is used for adjusting the packing around the stem the handle attaches too. This packing keeps water from leaking around the stem but not all stems use a packing and have a packing nut, some use o-rings instead. Turn the stem to the on position and use the adjustable wrench on the bonnet nut to remove the stem from the faucet. Once the stem is removed you can look into the hole the stem was removed from and see the seat down inside. The seat is the part that the rubber washer on the end of the stem presses against to shut off the water. The seat will have in the center hole of the seat a place where the seat wrench fits in tightly to unscrew the seat. There are several types of places for the seat wrench to fit. Some may look like an allen wrench would fit, others may have a square hole, or, even four evenly spaced grooves. You will need to select the proper wrench to fit the seat or, it will strip out ruining the faucet. Once the seat is removed you should check the condition of the stem and the seat. Unscrew the stem from the bonnet and inspect the stem for wear. Pay particular attention to the threads on the stem for wear, and look at the condition of the washer retainer cup for chipped or missing sections, try removing the screw holding the washer on. If the condition of the threads is bad or, the retainer cup is bad or, the washer screw breaks off and can’t be removed, the stem should be replaced. I like to replace the seat but if the replacement seat cannot be found in many cases they can be rubbed on some emery cloth or plumbers cloth until smooth and reused. If you are reusing the stem you must find the correct size washer and
To find a replacement stem and seat you will need to find a hardware store or, plumbing supply house that has the replacement stems and seats you need bring the stem and seat with you. You will need to identify the stem and seat and find the exact replacement parts there are many subtle differences in sizes and threads, there is no such thing as close they must be exact. Usually there will be at least one person there that is the expert at faucet stems and seats that knows all the differences between them and can quickly identify what you have. Often the hot and cold stems will have different parts as they many times turn in the opposite directions. Many places will have a small selection of stems and seats but if you have one that is uncommon they will usually be very helpful referring you to a hardware store or, supply house in the area that has a good selection. Faucet stems are somewhat of a niche market and the places that have a small selection will usually be quite helpful in telling you where to go to find a place that has a large selection. There are also quite a few on-line places that sell stems and seats such as New York Replacement Parts Corp. and Alfano Plumbing Parts, which have large selections.
Once you have either obtained replacement stems and seats or reconditioned the old stems you are ready to reassemble the faucet. This next step should be done on both new and, old stems. Lubricate the stems! Use plumber’s grease on the stem threads and on the stem where it goes through the packing to allow it to easily turn. This enables the faucet user to feel the washer contact the seat and know when to stop turning the faucet closed, which will help save the washer from damage from over-tightening. I like to apply Teflon paste to the seat threads, it is not needed as a sealant, but will aid in future repairs by lubricating the threads. Put the seat on the wrench then screw it in by hand until it bottoms then snug it with the wrench to avoid damage from cross threading. Move the stem to the on position, then make sure the bonnet washer is in place, and screw it into position with the adjustable wrench and tighten. Temporarily place the handle on top and move the stems to the closed position. Once both sides are completed turn the stop valves back on. If the faucet has a packing nut you are now ready to adjust the packing. Turn on the faucet and while the water is flowing and check for any leakage coming up between the stem and the packing. Tighten the packing nut very slightly just enough to stop any leakage. Do not over-tighten the packing or, the handle will become difficult to turn and the packing will wear causing leaks quickly. Turn off the faucet and put the handles in the correct orientation then secure them in place with the screws.