Pop-up Drain Stopper Repair

Begin by unscrewing the drain flange from the sink basin. This may require a drain wrench or pliers. Once the flange is removed, reach into the drain opening and disconnect the pop-up stopper from the horizontal pivot rod. Then, unscrew the pivot rod nut from the underside of the sink and remove the pivot rod. Finally, pull the entire drain assembly out from the top of the sink.

Using a scrub brush and a cleaner, scrub the inside of the sink drain opening and the exterior of the drain components. Remove any mineral deposits, soap scum, or old plumber's putty. Rinse all parts thoroughly with water and dry them completely with a clean rag.

With the drain assembly components separated, manually push the pop-up stopper down into the drain opening to ensure it creates a watertight seal. Then, pull it up to confirm it disengages and allows water to flow freely. This step verifies the stopper itself is functional without the lift rod.

Insert the drain pipe back into the drain opening from the top, ensuring it sits correctly. From underneath the sink, re-secure the drain pipe using its nut. Do not reinstall the pivot rod or the lift rod mechanism. Ensure the drain flange is seated properly in the sink basin.

Run water into the sink and allow it to fill partially. Manually push the pop-up stopper down into the drain opening with your finger to seal it. Check for any leaks around the drain flange from underneath the sink. If there are no leaks, let the water drain by manually lifting the stopper. Ensure it lifts freely and allows complete drainage.