Removing a tub drain is necessary if you're removing or replacing the bathtub. It's also necessary if the drain fitting is badly corroded or leaks and needs to be replaced. The drain fitting is a metal basket-like piece that has a lip or flange at the top and a body with threads on the outside. It screws into the elbow, or shoe, of a horizontal length of pipe that extends toward the end of the tub and ties into the drain pipe assembly.
Inside most drain fittings are two metal crossbars that form an "X" to prevent large items from falling into the drain. The crossbars are what make it possible to remove the drain with a plug wrench or pliers.
A plug wrench is a small wrench made of cast iron or steel that is milled to fit the crossbars of two or more different sizes of drains. If you expect to be removing your tub drain more than once, it will be worthwhile to purchase this inexpensive item. Also, because the head is form-fitted to the drain's cross, there is less chance of accidentally breaking off the cross.
Short of a plug wrench, the best substitute is a set of needle-nose locking pliers. The pliers need to be small enough to reach into the drain and through the cross. Once the locking pliers are secured, you use a pair of standard pliers to turn the locking pliers and loosen the drain.
If your drain doesn't have crossbars, you'll need to use a tool called a tub drain extractor. It has a conical shape and helical knurls that grip the metal wall on the inside of the drain fitting. You turn the extractor with an adjustable wrench.
Tub drains are stubborn, often due to corrosion, gunk, or hardened plumber's putty. Heat helps to loosen old plumber's putty. If the tub is very cold, gently blow warm air from a heat gun or a hair drier over it for a few minutes to soften the putty before removing the drain.
Equipment / Tools
- Small flathead screwdriver
- Plug wrench
- Adjustable wrench
- Locking needle-nose pliers
- Standard pliers
Remove the Tub Stopper or Screen
Remove the drain stopper or screen to gain access to the tub's drain fitting. If the tub has a screen, simply pry underneath the screen with a small flathead screwdriver to pop it off. Tubs with screens usually have a bucket or plunger stopper assembly that stops the water inside the drain pipe.
If the tub has no screen, it likely will have a stopper set into the drain opening. The method to remove it depends on the stopper type. Stoppers that you open and close by moving the stopper itself usually unscrew from the drain or are secured with a setscrew. Stoppers that you operate with a lever on the overflow drain plate may have a metal rocker arm that extends through the horizontal portion of the tub drain pipe. Carefully pull the stopper and rocker arm from the drain.
Remove the Drain With a Plug Wrench
Insert the end of the plug wrench into the drain opening so the tines on the wrench fit onto the crossbars of the drain. Most plug wrenches have more than one size of head; use the head that makes the snuggest fit.
Turn the plug wrench counterclockwise with a large adjustable wrench or tongue-and-groove pliers to loosen the drain. Unthread the drain all the way by hand once it is loose enough.
Remove the Drain With Locking Pliers
Insert a pair of locking needle-nose pliers into the drain opening as far as the jaws will go. Make sure the jaws are on opposite sides of the crossbars, over the center of the "X". Clamp the locking pliers so they grip the crossbars tightly.
Grip the locking pliers with a set of standard pliers, grabbing as low as possible on the locking pliers so that they do not interfere with the locking action. Turn the pliers counterclockwise. Be patient and go slowly.
After a few rotations, the tub drain should be loose enough that you can set aside the second set of pliers and turn the locking pliers by hand.
Clean the Drain Opening
Use a flathead screwdriver or a putty knife and a rag to remove the old ring of plumber's putty from around the drain opening. Try not to let the putty fall into the drain because it never breaks down and could start a clog.
If you're replacing the old tub drain with a new one, take the old piece to the store with you to be sure you get the right replacement part.