Caulking a Cracked Toilet
- 1). Turn off the flow of water to the cracked toilet using the shut-off valve beneath the tank, and then flush the toilet to drain the water from the tank. Remove the pipe supplying the water to the tank using a crescent wrench. Take off the lid of the tank and place it onto a flat surface out of the way of your work.
- 2). Dry out the inside of the toilet tank with towels or a sponge, removing all present water. Wipe the outside of the tank with the towels as well to ensure that it’s dry also, especially over the cracked area. Complete the drying process by using a hair dryer on both the inside and outside tank surfaces to remove any remaining moisture.
- 3). Place a tube of silicone caulk into a caulking gun. Press the caulking gun trigger several times to move the plate at the rear against the base of the tube. Cut the tip off the tube at a 45-degree angle with a utility knife, leaving an opening of about 1/4 inch in diameter.
- 4). Cover the crack with a bead of caulk beginning 1 inch before the start of the crack and extending 1 inch beyond the crack’s end. Spread the caulk over the cracked area with a putty knife to cover the crack completely with a flat layer of caulk. Allow the caulk to dry for 24 hours.
- 5). Reconnect the water supply, and open the shut-off valve to refill the tank. Watch for any leakage through the caulk patch. If none occurs, the caulking was successful and you can use the toilet as normal. If there is further leakage, repeat the patching process again to fill the area missed with the first caulk application.
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