This article will show you how to perform simple repairs on a leaking outdoor faucet that has an anti backflow/vacuum breaker feature. This feature is to help prevent water from siphoning back into the public water supply should the public water supply fail. It also helps the valve from being damaged should the fixture freeze.
If the valve is leaking while the water is turned off, it is a separate problem from the valve leaking while the water is turned on. Both have different repair methods.
If the water faucet is leaking while the handle is in the off position, the rubber grommet or the cartridge is in need of replacement. To resolve this problem, simply turn off the water at the street, unscrew the handle and pull the handle out. At the end, you will find either a rubber washer or a cartridge of some kind. The rubber washer is a universal replacement style. The cartridge is longer lasting, but more expensive. Sometimes the parts are no longer available and the entire assembly must be replaced.
If the outside water faucet leaks from around the vacuum breaker while the faucet is turned on, this is a waste of water and a waste of your money. These faucets can be tricky to get apart. It looks as if you simply unscrew the cap and see the inside of the faucet. Keep going. This is little more than a cover to the plastic assembly.
Take two flat screwdrivers and insert them in the holes and use a third screwdriver to unscrew that assembly. All that is inside is a rubber o-ring and a rubber washer. Both of them are replaceable. If you have the mechanism that is attached to the outside of the faucet, simply remove the entire assembly with a Allen Wrench or a Torx Wrench and install a new assembly available from your local big box store.
For more in depth information about fixing a leaking outside faucet, please visit http://www.single-family-home-remodeling.com/outside-faucet.html
Also, check out http://www.single-family-home-remodeling.com for other home remodeling and repair information.