How to Repair a Leaking Toilet Base

A toilet is sealed to the top of the drain pipe with a wax ring that sits between the toilet base and the drain flange. During installation, the ring would compress, creating a watertight connection, but over time, this ring would dry out, harden and then crack due to a rocking bowl, causing leaks around the toilet base. Fortunately, it is quite easy to fix such a problem, where you just have to replace the worn-out wax ring. Here is how to repair a leaking toilet base:

1. Secure the things that you will need, including a wrench, putty knife, rag, towel, replacement wax ring, caulk and caulking gun (optional), and plastic shims (if needed).

2. Shut off the water supply to the toilet tank by turning the water shut-off valve handle clockwise, which you can find under the tank. Empty the bowl and tank by flushing the toilet.

3. Using a wrench, loosen the supply line nut connecting the shut-off valve to the toilet tank fill valve. Do it until the line pulls free from the tank’s connection point. Another method that you can try is removing the bolts that secure the tank to the bowl, lifting the tank off and then setting it aside, which makes it easier for you to remove and reinstall the bowl. Wipe up any water that is spilled from the line with a towel.

4. Loosen the two nuts holding the toilet base to the floor and remove them. If you find the nuts covered by caps, simply pry the caps up using a flat-head screwdriver to have access to the nuts. Carefully lift the toilet straight up and then position it on its side to expose its underside—you might want to seek help from another person for this, as toilets can be heavy. Stuff the exposed toilet flange with a rag to prevent gases and odors from entering your home.

5. Scrape off the old wax from the toilet base and the flange with a putty knife, removing as much of the material as possible. Also, get rid of any old caulking from the base and the floor.

6. Place the new wax ring over the hole on the toilet base and press it firmly with your hands, while doing it gently not to smash it out of shape. After this, you can then remove the stuffed rag from the toilet flange.

7. Re-install the toilet by lifting it up and centering it over the flange bolts. Set it down slowly and gently, ensuring that the wax ring is centered over the flange. Press the bowl down firmly so that the wax expands and seals the gap between the toilet base and the flange.

8. Re-install the nuts onto the flange bolts and tighten them up just enough that you will not crack the base. Rock the bowl back and forth to see if iut moves, and if it does due to an uneven floor, you can place a plastic shim under the toilet base to stabilize it.

9. Reconnect the water supply line and turn the water supply on. Check for any leaks to avoid having such a problem after you have installed everything. If you want, you can caulk along the toilet base to be able to detect a leaking wax seal.

By following this guide, you will be able to repair a leaking toilet base.

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