Bathroom sink stoppers can fail to work properly in two ways. Either you cannot get them to close properly, or you cannot get them to open up and drain the sink. There are also times when they only open a tiny bit, causing the sink to drain slowly, leaving an unsightly coat of soapy sludge behind. Repairing a bathroom sink stopper isn't difficult, but it might requires a small amount of exertion in order to make a proper repair. By that I mean that you might have to crawl on the floor and into the sink's cabinet in order to reach the stopper's attaching hardware. If you cannot do this on your own, you should enlist someone's help to do so.
A sink stopper is a simple mechanism of four components, so let's take a look at how it works from the top down. The first component is the pull up/push down rod, called a stopper rod or a lift rod, which opens and closes the stopper by lifting. The second component is an attaching lever, called a Clevis that connects the lever to a small rod, called the Pivot rod that lifts and lowers the stopper from below. The pivot rod passes through the drain pipe and has a ball mounted on it.
The pivot rod is attached to the clevis with a spring clip (on newer types of drains) or a thumb screw. In turn, the clevis is attached to the stopper or lift rod with a clevis, or set screw, which may be a thumb type screw. The clevis is raised or lowered to the proper height by adjusting the point where the clevis attaches to the stopper rod.
A pair of channel lock pliers is the only tool you'll need for this repair.
Begin by inspecting all the components for proper connection. Oftentimes the clevis or the spring clip will have slipped out of place, causing the stopper to not rise as far as it should. You may have to have someone raise and lower the stopper rod while you are observing how the four components work together. If everything appears to be working, but the stopper still doesn't engage properly, it's time to take a closer look at the pivot rod.
Using the channel lock pliers (or any suitable pliers), remove the pivot nut that attaches the pivot rod to the sink's drain pipe. This is normally a large knurled or hex-nut and has to be reached from behind the drain pipe. Remove the spring clip and disconnect the pivot rod from the clevis. You can easily disconnect and remove the stopper from the pivot rod by twisting it after the pivot rod is disconnected from the clevis.
Be sure to clean up the stopper and inspect it for signs of damage. If the edge of the stopper is damaged, or it shows signs of corrosion (metal stoppers) it should be replaced. The plastic stoppers found in today's sink naturally don't corrode, so they can potentially last for years.
Next, remove the pivot rod and inspect it for signs of corrosion. Overtime the combination of chemicals that are occur naturally in our soap, water, toothpaste and household cleaners, including bleach, can cause the tip of the pivot rod to corrode to the point where it is not making a solid connection to the plunger. If you think that is the case, you have to replace the pivot rod, which means making a trip to the local hardware or plumbing supply store.
Pivot rods come in different sizes, so it's a good idea to take you old pivot rod along with you for comparison with the variety of pivot rods available at the store. Once you have the proper replacement on hand, return to the sink and install the new rod. Connect the pivot rod to the clevis using the spring clip after making sure that the stopper is properly connected to the pivot rod. Tighten the pivot nut enough to make a good seal, but do not over-tighten it.
After reconnecting all the components together, check the assembly for proper operation. Check for a good seal by adding some water to the sink with the stopper closed. It should be tightly seated and the sink should hold the water without leakage. Then open the stopper by pushing down on the lift rod. The stopper should rise far enough to allow the sink to quickly drain its contents. Finally, check for leaks beneath the sink basin and around the drain pipes. It wouldn't hurt to check the trap connections for proper alignment and leaks at this time.
This completes a look at how to properly repair a sink stopper. I hope that you have found this article useful.