Replace Bathroom Sink Drain Assembly

A functional drain assembly is essential for a smoothly running bathroom sink. Over time, however, these assemblies can become clogged, corroded, or simply worn out, requiring replacement. Replacing a bathroom sink drain assembly is a relatively simple task that can be completed in under an hour with the right tools and materials.

Materials you'll need:

Replacement drain assembly
Adjustable wrench
Channel-lock pliers
Putty knife
Plumber's putty
Flashlight
Bucket

Steps:

Turn off the water supply: Locate the shut-off valves under the sink and turn them off to cut off the flow of water to the sink.
Remove the old drain assembly: Use the adjustable wrench to loosen the slip nut that holds the drain assembly in place. Once the nut is loose, pull the old assembly straight up and out of the sink.
Clean the drain opening: Use the putty knife to scrape away any old plumber's putty or debris from the drain opening in the sink.
Apply plumber's putty: Roll out a small amount of plumber's putty into a rope and then work it around the base of the new drain assembly. This will help create a watertight seal.
Insert the new drain assembly: Carefully insert the new drain assembly into the drain opening. Tighten the slip nut by hand until it is snug, and then use the adjustable wrench to further tighten it by about a quarter to half a turn.
Connect the drain pipe: Attach the drain pipe to the bottom of the drain assembly and tighten the nuts by hand until they are snug. Use the channel-lock pliers to further tighten the nuts by a quarter to half a turn.
Test the drain: Turn on the water supply and run water into the sink to test the drain. Check for any leaks around the drain assembly or drain pipe.

Tips:

If you have difficulty loosening the slip nut, try using a penetrating oil to help loosen it.
If you are replacing the drain assembly due to a clog, be sure to clean the trap and drainpipe as well to prevent future clogs.
If you are not comfortable replacing the drain assembly yourself, contact a licensed plumber for help.