I search in online, My answer is listen in on off the decorative cap on the contend with, cast off the address screw, pull off the cope with and use a crescent wrench to unscrew the packing nut. After unscrewing the stem, cast off and replace the seat washing machine held in location by manner of a brass screw.
Before You Start
• Shut off the water under the sink.
• Close the sink drain; cover it with a rag to catch dropped parts.
• Tape the jaws of your wrench with a layer of duct tape to avoid scratching the fixture.
• Establish a place to lay out parts in order of removal.
• Use distilled white vinegar and a soft scouring pad for removing mineral deposits on faucet parts.
First, find Your Faucet. There are four kinds of faucets: compression, cartridge (sleeve), ceramic disk, and ball type. Each type is illustrated here. Except for the ball-type faucet, there are two illustrations for each. The less detailed version will identify the kind you have. The more detailed one will help as you make repairs. A compression faucet relies on rubber washers to seal the valve seat. Rubber washers wear out and must be replaced occasionally. The other types, often called washerless faucets, last longer but they too can develop leaks. When these cartridge, ceramic-disk or ball-type faucets leak, you can either replace the O-ring or neoprene seal that's causing the leak or replace the entire assembly for less than $20.
Most leaky compression faucets need new seat washers. Pry off the decorative cap on the handle, remove the handle screw, pull off the handle and use a crescent wrench to unscrew the packing nut. After unscrewing the stem, remove and replace the seat washer held in place by a brass screw. Coat the washers with nontoxic, heat-proof plumber's grease. Pop the stem out of the packing nut and replace the O-ring, the culprit for leaky handles. O-rings range in size from 3/8 to 5/8 in., so it's crucial to exactly match the size on your faucet. Coat the new O-ring with the plumber's grease. Reassemble the faucet and tighten the packing nut. If your faucet continues to leak, the seat may be pitted. Remove the stem and grind smooth the valve seat with a valve-seat dresser, a tool you temporarily screw down into the faucet. Also this only for Compression Faucets. If you have any other type I suggest visiting: https://www.thisoldhouse.com/ideas/fixing-leaky-faucet
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