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Plumbing 101

Photo by Craig Raine

Compared with some of the headaches that go along with home ownership, a leaky kitchen faucet or toilet tank valve is a minor problem. Yet a steady trickle of water is a waste of both water and money, and eventually it will get on your nerves. Both of these problems can be fixed quickly, and unlike many more involved plumbing jobs, these repairs require only a few ordinary tools. For foolproof instructions, we called on a pro who performs these repairs on a regular basis—David Sorrell, of Goodhill Mechanical Contractors in Woodbury, Connecticut.

Replacing a Flapper Valve

Photo by Geoffrey Gross

When water seems to trickle through a toilet long after it has been flushed, a worn rubber flapper valve at the bottom of the tank is probably to blame. When you flush the toilet, the flapper lifts, letting water flow into the bowl. As the tank empties, the flapper sinks to block the opening, which allows the tank to refill. Although durable, the flapper can wear out over time, providing a less-than-perfect seal. The result is an audible trickle, punctuated by an occasional surge of supply water topping off the tank. You might be able to get the trickle to stop by jiggling the handle, but eventually this trick stops working. A faulty flapper valve can drive up water costs, and if the supply line is plumbed with warm water to prevent condensation, heating costs will go up, too.

Changing an old flapper for a new one ($5 or less) is a quick job. Begin by closing the supply line to the tank. If the valve looks corroded or weak, Sorrel recommends turning off the water at the main, not at the tank.

Similar But Not Identical

Photo by Geoffrey Gross

Flapper assemblies differ slightly depending on the make and model of toilet. But the basic process of replacing them is the same.

Replacing the Valve

Photo by Geoffrey Gross

There are many makes and models of toilet, but the flapper-valve assembly will look basically the same. Removing the rubber flapper from the assembly is easy. Some snap off and require no tools; others are held in place with a machine screw.

Although generic flappers are available, stick with the part made for your toilet—provided you can find a replacement. Note the brand of toilet, and take a look at the valve assembly before you shop. Better yet, take the flapper with you to be sure you get the right one. Plumbing jobs are famous for prompting repeated trips to the store for more parts. But there's no need to visit more often than you really have to.

Shown: The flapper on this flush assembly pops off without any tools. Simply replace the old flapper with a new one. Be careful not to break off the barbed plastic pin.

A Plumber's Trick

Photo by Geoffrey Gross

Use emery cloth to smooth any rough edges around the lip of the valve seat that would prevent a watertight seal between the flapper and the seat.

The Drip That Drives You Crazy

Photo by Geoffrey Gross

Time, use and water that is overly acidic or mineral-laden can wear out the type of single-lever valves now common on sink faucets and shower controls. When the lever is pushed all the way down and the faucet continues to drip, the culprit is a worn valve-stem assembly. You can swap this worn part for a new one in about 20 minutes, and without any under-the-sink gymnastics.

Replacement Cartridges

Photo by Geoffrey Gross

Actually, it could take you longer to find the right part than it does to make the repair. Most major faucet manufacturers make single-lever faucets, and replacement parts are widely available at home center and hardware stores, but the valve assemblies are not interchangeable. Even different faucet models from the same manufacturer are likely to require different valve replacement parts. It will be easier to get the right parts if you know the name of the manufacturer and the faucet model number. If you know the manufacturer but not the model, a local plumbing-supply house might be able to narrow the choices for you. If all else fails, pull the old part before buying a new one. That's not the most convenient option, Sorrell says, but at least it's foolproof.

We used a Moen faucet for the steps shown here. If your faucet is from a different manufacturer, the parts will look a little different. But, according to Sorrell, the procedure for replacing them is virtually the same. Cartridges are available in both plastic and brass; plastic cartridges work just as well as their brass counterparts, and they are a few dollars cheaper. If you have well water, Sorrell suggests the plastic model because it is less susceptible to damage from untreated water.

Pop the Faucet Cap

Photo by Geoffrey Gross

Your first step is to shut off both hot- and cold-water supply lines under the sink, and here Sorrell advises caution. Shutoff valves in older plumbing systems can be corroded, especially when connections are threaded instead of soldered. "I've had them crumble right in my hands," Sorrell says. An uncontrolled geyser under your sink is no way to get started, so if the shutoff is suspect, use the main shutoff valve, located where the waterline enters the house or at the pressure tank. Another preliminary step: Block off the sink drain with a rag so small parts don't disappear.

Pop to the cap on the top of the faucet with a screwdriver or utility knife, then remove the single screw to free the faucet lever. You might need to work the lever back and forth gently to pull it up.

Free the Retainer Nut

Photo by Geoffrey Gross

Use slip-joint pliers to free the retainer nut uncovered when you removed the lever. You will cover this nut when you reassemble the faucet so don't worry about marring the finish.

Replace the O-Rings

Photo by Geoffrey Gross

While you have the spout off, Sorrell suggests you replace the O-rings on the body of the faucet, which prevent leaks at the base of the faucet. You can buy O-ring kits where you buy cartridges. Use a small screwdriver to ease off the old rings. Install new ones with lubricant supplied with the replacement kit.

Remove the Old Cartridge

Photo by Geoffrey Gross

Remove the cartridge, but first note the location of the small notch at the top of the stem. When you install the new cartridge, make sure the notch points in the same direction. Plumbers use a special tool to pull the cartridge from the faucet, but pliers also will work (it just might take some wiggling to break the tension). Retrace your steps to install the new cartridge.

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