- Jolly Plumbing and Heating, Inc.
How to Fix a Leaking Toilet
Updated: Oct 17, 2022
Troubleshooting The Porcelain Throne
There may be no use crying over spilled milk, but a leaking toilet can certainly frustrate a person to the point of tears. If you’re dealing with a leaky toilet, we’re here to help! Below are some common problems, how to diagnose them, and how to fix each one. We always recommend having a professional handle issues like this for you, but if you’d like to attempt this on your own, we’ve provided a general overview. Don’t hesitate to call us at any point during the process – you’ve got enough in life to worry about; let the plumbers handle the dirty work!
Common Problems
If your toilet is leaking out water, it’s likely because of one of these problems[1]:
Faulty seal
Broken overflow tube
Broken gasket (seals connection between tank and bowl)
Faulty closet flange (toilet not properly anchored to the floor so there’s a gap in the connection between the toilet and drain pipe)
The best way to diagnose which of these problems is causing your leak is to run through a quick checklist. Keep reading to diagnose your issue!
Diagnosing the Cause of a Leaky Toilet
Faulty Seal
The seal refers to the wax ring that closes the connection between the base of your toilet and the drain.
Are you consistently finding water on the floor of your bathroom?
Have you noticed any leaks from the base of your toilet?
Is your toilet loose (wiggles upon touch)?
Do you see any water stains around the base of your toilet?
If any one or more of these is true of your situation, you may need to replace your wax seal!
Broken Overflow Tube
The overflow tube is what stops your tank (the top portion of your toilet) from overflowing with water.
Is your toilet bowl filling with too much water?
Is your tank water not properly draining into your toilet bowl?
Either of these could indicate a problem with your overflow tube. The overflow tube is what siphons tank water into your toilet bowl. If the overflow tube is too high, your toilet bowl could fill with too much water. If your overflow tube is blocked or malfunctioning in some other way, it may not drain water into your bowl, causing an excess of water in your toilet’s tank.
Broken Gasket
The gasket is what seals the connection between the tank and the bowl. If it comes loose or malfunctions, it can allow water to seep out of the middle of your toilet.
Is water seeping out from the base of your toilet tank?
Does the tank wobble?
Either of these could indicate a broken toilet gasket. Like the wax seal at the base of your toilet, it prevents water from releasing onto the floor. The connection needs to remain air tight in order to prevent leaks, so if the gasket cracks or the connection becomes loose, that could be why you are experiencing toilet leaks.
Faulty Closet Flange
The closet flange is necessary to bolt the toilet to the floor. Without a working closet flange or bolts, the water from the toilet bowl can miss the drain and spill onto the floor.
Is there a bad odor in your bathroom?
Is water pooling up at the base of your toilet?
Does the base of your toilet wobble?
Are there water stains near the base of your toilet?
This is one of the worst parts of your toilet that can leak. Instead of going directly into the sewer drain, the used toilet bowl water can seep onto your bathroom floor.
DIY: How to Repair Toilet Leaks
Now that you know the common problems that cause toilet leaks and have diagnosed what your toilet’s issue is, it’s time to fix it.
How to Fix a Faulty Toilet Seal
Determine what type of wax ring your toilet needs. The diameter is what will differ. Look up your toilet make and model to see which ring diameter will fit yours.
Determine why your ring failed in the first place. If your toilet also wobbles, make sure you bolt it down tighter, as the wobbling can wear down the ring prematurely. Wax rings also harden and crack over time.
Drain the toilet bowl and tank.
Unhook the water supply.
Remove the bolts that attach the base of the toilet to the floor and lift the toilet up and away from the connection.
Remove the faulty ring and scrape away any leftover wax deposits.
Replace with a new ring and reattach the toilet securely to the ground. Make sure it does not wobble.
Reattach the water supply.
Flush the toilet to refill and monitor for leaks.
How to Fix a Broken Overflow Tube
Turn off the water supply.
Flush your toilet to remove the water from the tank.
Remove the tank lid and locate the overflow tube (it’s in the middle between the fill valve and the float ball).
Remove and replace the overflow tube using these instructions.
How to Fix a Broken Gasket
Turn off the water supply.
Flush your toilet to remove the water from the tank.
Separate the tank from the bowl.
Remove the existing gasket and take that to your local hardware store. An employee can help you locate the correct replacement part.
Attach the new tank-to-bowl gasket. Tighten and make sure it can’t move around.
Reattach the tank to the bowl and make sure it doesn’t wobble.
Reattach the water supply and flush the toilet. Monitor for leaks.
How to Fix a Faulty Closet Flange
Turn off the water supply.
Flush the toilet to empty the tank.
Remove the wax from the flange as much as you can (try a paint scraper).
If the flange has minor issues, such as a break in just one of the tracks, you may be able to remedy with a repair plate. If the damage is worse, you may need a new ring or flange replacement.