Lever kitchen faucets are prone to leaking when their washers become worn and damaged. Changing a lever kitchen faucet washer yourself is not difficult and can save you money. All that is required is a set of basic tools.
Turn off the water line. Look underneath your sink and check for a shut-off valve. If you don't see one, find the main water source and turn off the valve. Test to make sure the water is off.
Turn the faucet on to drain out any water still in the line.
Put a rag or drain stopper in the drain of your sink so you don't lose any small parts when disassembling your faucet.
Set another rag down on a counter or other flat surface and line each of your parts up on the rag in order. This will help avoid confusion when you're putting the pieces back together.
Use an Allen wrench to loosen the screw holding the kitchen lever in place.
Remove the screw and twist the handle off. If the handle won't come off, cover it with a rag and use a pair of pliers to gently remove it. This will ensure you don't scratch the finish on the faucet.
Remove the packing nut on top of the stem assembly with a pair of pliers.
Pull out the entire stem assembly.
Locate the small screw at the bottom of the stem assembly holding the washer in place and unscrew it.
Take the entire stem assembly and washer to a hardware or home improvement store and purchase a replacement washer that is an exact match.
Replace the old washer with the new one.
Put the stem assembly and faucet back together in reverse order.
Turn the water back on at the main source.