Most bathroom sink drains come in three pieces. They are the top head piece with a flange, the pop-up assembly body, and the tail piece.
Before installing the sink drain make sure the surface area that contacts the sink drain is clean and the old putty completly removed.
The tools you will need for installing a bathroom sink drain are plumbers putty
, thread tape, plumbers pipe dope
, crescent wrench, and a pair of channel-lock pliers.
First install a 1/4" in diameter bead of plumbers putty around the underside of the sink drain flange where it makes contact with the sink. From the top side of the sink, insert the sink drain flange into then drain hole.
Install the lock nut onto the pop-up assembly body screwing it all the way down onto the pop-up assembly. Install the rubber gasket around the pop-up body on top of the lock nut, apply a generous amount of pipe dope to the top of the rubber gasket.
Next take the pop-up assembly body and screw it into the sink drain flange. After tightning the flange body to the pop-up assembly position the hole for the pivot rod to the back of the cabinet, while holding the pop-up assembly body tighten the lock nut that fastens the drain to the sink.
Wrap thread tape around the threads of the tail piece and apply pipe dope over the thread tape. Insert the tail piece into the pop-up assembly body and tighten. Be careful not to over tighten.
Insert the horizontal pivot rod into the hole on the back of the pop-up body and hand tighten the pivot nut, if after installation of the push rod assembly the vertical push rod is to hard to operate loosen the pivot nut a 1/4 turn.
Insert the vertical push rod into the hole on top of the faucet. Install the push rod clevis on to the vertical push rod. Using the metal clip insert one side of the metal clip onto the end of the horizontal pivot rod, then insert the clevis onto the pivot rod and trap the push rod clevis between the two ends of the metal clip onto the horizontal pivot rod.
After installing the bathroom sink drain and reinstalling the trap, check for leaks around the sink drain by plugging the sink drain and fill the sink with water. Check under the sink around the bottom of the drain for leaks, the common cause for leaks around the drain is the lock nut needs tightened.
To remove a sink drain you would first disconnect and remove the trap. Then in reverse of the steps above remove the vertical push rod and horizontal pivot rod connections to the drain.
After loosening the lock nut, hold the sink drain flange from the top side of the sink. Turn the pop-up body disassembling the drain flange from the pop-up body.