How to Fix a Leaking Toilet

Tips for Determining and Fixing a Leaking Toilet

By Mark J. Donovan

A leaking toilet can occur for a few reasons. It’s important, however, to first find out if the toilet is indeed leaking, or if it is simply sweating due to condensation issues. If the bathroom air is hot and humid, and there is cold water in the tank, then it is very likely your toilet is simply sweating.

To rule out a leaking toilet first examine the toilet to see if you see beads of water all around the toilet tank. If so chances are it is a condensation issue that your toilet is experiencing.

You can rule out a leaking toilet by letting the water fill up in the tank and allowing the water time to warm up to room temperature.

Once the water has reached room temperature you can then wipe down the sides of the tank. Come back an hour later, and if you see no moisture on or around the toilet, you most certainly do not have a leaking toilet.

Toilets leaks are typically related to three situations. First, the toilet wax ring may have failed. The toilet wax ring sits underneath the toilet bowl and forms an air tight seal with the toilet trap. If the wax ring fails, or the toilet bowl screws that hold the bowl to the floor are loose, water can seep around the edges of the toilet bowl.

You can check for this type of leak by using a paper towel and slipping it under and around the toilet bowl base. If you see moisture on the paper towel chances are the toilet bolts are loose and/or the toilet wax ring has failed.

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Try gently tightening the bolts. If that does not solve the problem see my “Changing a Toilet Wax Ring Ebook” to learn how to replace the wax ring.

The second area where toilet leaks spring up is where the toilet tank connects to the toilet bowl. There is a rubber toilet tank gasket that connects the two that can break down over time. Look carefully around the base of the toilet tank and the back edge of the toilet bowl to see if any leaks have occurred.

If so, you can try gently tightening the bolts that connect the tank and bowl together, but be careful to not over-tighten. You could crack either the toilet tank or bowl. If tightening up the bolts does not help, you will need to turn off the water supply to the toilet, drain the tank and replace the toilet tank gasket between the tank and the bowl.

The third area where toilets leak is around the water supply line, either up under the toilet tank base, or near the valve area. Sometimes you can resolve the problem by tightening up the associated nuts with a pair of adjustable pliers. Other times you may need to get an entirely new supply line.

Toilet Wax Ring Replacement Ebook

The last possibility is that there may be a hairline crack in the toilet tank or bowl. Again, carefully inspect the tank for any cracks. If you see any, you will need to replace either the tank or bowl, depending upon where the crack is.

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