How to Replace a Kitchen Sink Strainer Basket

Strainer baskets are the workhorses of the kitchen, yet they are often ignored until a drip develops in the cabinet below. A leaky sink strainer is not just an inconvenience; it is a slow-motion disaster that rots vanity wood and corrodes metal piping. Replacing one is a straightforward task that breathes new life into an aging sink and restores your peace of mind. Done well, a new installation is completely invisible and drip-free for years. You are essentially creating a gasket seal between the steel of the sink and the body of the strainer. If you take your time cleaning the old residue and applying a generous amount of putty, you will never have to worry about this seal again.

1. Catch the water first. Place a bucket under the drain pipes to catch water. Use slip-joint pliers to loosen the nut connecting the tailpiece to the bottom of the strainer basket.
2. Unbolt the old strainer. Use a basin wrench or a pair of large channel-lock pliers to unscrew the large locknut holding the strainer assembly against the underside of the sink. Slide the friction washer and rubber gasket off the threaded tail.
3. Strip it to bare metal. Push the old strainer up and out from the sink basin. Use a putty knife or a non-scratch scrub pad to remove every trace of old putty or silicone from the sink drain hole.
4. Create the seal rope. Roll a golf-ball-sized amount of plumber's putty into a long, thin rope about the thickness of a pencil. Wrap this ring of putty around the underside of the new strainer flange.
5. Lock it down tight. Press the new strainer into the sink hole firmly. From underneath, slide the new rubber gasket and friction washer onto the threads, then thread the locknut on by hand until it is snug.
6. Test and reconnect pipes. Wipe away the excess putty that has squeezed into the sink basin. Reattach the tailpiece piping to the bottom of the strainer and tighten the slip-joint nut.