Outdoor faucets are handy for doing work such as gardening and washing your car. The handle on these faucets is connected to a part called a valve stem, which controls the flow of water out of the end of the faucet. Turning the handle opens and closes a washer at the end of the stem and regulates the water pressure. Because these faucets are outdoors and exposed to the elements, they eventually can break down or leak. If that happens, you can change out the faucet stem for a repair.
Turn off the water supply to the outdoor faucet you want to change. Some outdoor faucets will have a water supply valve while others will not. You can determine whether your outdoor faucet has a supply valve by tracing the water supply pipe backwards into your house. In this case, the valve might be in a basement. The water supply valve will be a circular knob and valve attached to the pipe. Turn off the water supply by turning the supply knob clockwise.
Turn off the water supply to your entire house. This step is necessary for homes with slab foundations, in which there will not be a water shut-off valve. You will need to turn off all the water supply. Look for a water utility box in the street near the front curb of your house. Turn off the water by rotating the water supply knob that is attached just behind the water meter.
Remove the packing nut. This is the hexagonal nut located just behind the faucet handle. Twist it counterclockwise with the adjustable wrench to remove.
Pull the faucet handle and valve stem out of the faucet.