Why Won’t My Toilet Stop Running?

Are you tired of constantly hearing your noisy toilet after you flush? A running toilet is frustrating, and can drive your water bill through the roof. If you notice some extra sounds after you flush where there should be silence, you have a running toilet on your hands.

A constantly running toilet can cause a huge water bill and even other costly damages like water pipe damage. It may sound intimidating to fix, but don’t worry. There’s plenty of steps you can take to diagnose your toilet problem before throwing in the towel and calling an expensive plumber.


What Qualifies as a Running Toilet?

A running toilet will continue to fill with water after a toilet flush, even when it should’ve stopped. Since the problem is so common and may seem minor, many home-owners don’t notice the issue until it’s too late. If you notice something off about your toilet, you should check it out before it becomes more troublesome (and more expensive).

What Causes a Running Toilet?

parts of a toilet

There’s plenty of reasons you might have a constantly running toilet. Multiple different components may be causing the issue; fortunately most of them are easy for you to troubleshoot at home. They could be things like a faulty fill valve, a leaky flapper, or even the float level.

The Flapper or the Flush Valve

The most common issue comes from something called the flapper. The flapper is a rubber piece that lets water from the toilet tank into the bowl. There’s another device called the flush valve. The flush valve empties the toilet tank if it’s full. Both of these pieces can wear out gradually, leaving you with a running toilet.

To narrow down the issue, drop some food coloring or dye into the toilet tank. Give it 20-30 minutes and come back to take a look. If you notice some colors in the toilet bowl, that means there is water leaking from your tank. This is a pretty good guarantee that your flapper or your flush valve is faulty.

The Flapper Chain

The flapper chain runs from your flush handle to the flapper. When you push down the handle, the flapper chain lifts up the flapper, triggering a toilet flush. A chain that is too long or short won’t move the flapper like it should. Either way, a bad chain will create a constantly running toilet.

Check to see if your chain is tangled or is too tight on the flapper. If the flapper isn’t closed properly or the chain is too long, try to adjust it. If the chain is the root cause of the issue, adjusting it should stop your toilet problem. If not, you may have to delve deeper into troubleshooting.

The Float or Fill Height

Inside your tank is something called a float ball. The float is responsible for keeping the water level in your tank even. If the level is too high, this means that water will run into your overflow tube and into the toilet bowl so it doesn’t overflow the toilet tank. When this happens, you’re left with a running toilet.

Take off your tank lid and look for the overflow tube. If the water is an inch below the top of it, you’re all set. If not, try to adjust the float level. If the problem still persists, you might have to replace it.

The Fill Valve

Your toilet fill valve fills your toilet tank with water. It should stay running until the tank is full and then shut off. The problem begins when it doesn’t.

You can test for a faulty fill valve with a couple of easy steps. First, just remove the tank lid and flush your toilet. If there’s some noticeable leaks on the valve, it needs to be replaced. If you can’t see any that are visible, continue troubleshooting.

If there’s no visible leaks, lift the part that’s attached to the float while it’s still filling your tank. If the water stops, you’re good to go. If the water doesn’t stop, that means you’ve got another fill valve leak somewhere.

The Overflow Tube

The overflow tube runs water to fill the toilet bowl after you flush. There’s a small tube that connects the toilet overflow tube to the fill valve. After the toilet tank is refilled, water is pushed out and fills the toilet bowl.

Check in your tank to see if this tube is disconnected or looks like it’s not in the right place. If the tube is faulty, the toilet tank can’t empty and the bowl won’t be filled. Luckily, this is a relatively quick repair.

Corroded Toilet Handle

Does the toilet handle stick when you’re flushing it? This alone indicates just normal wear-and-tear, but can also be a contributor to the constantly running toilet issue. The longer your handle is stuck downwards, the longer your flapper is forced to be open, which lets more water into the toilet bowl than there should be.

If you give it a test toilet flush and your handle isn’t exactly the smoothest, that might be your issue. Replacing the handle is the only way to fix a corroded one.

How Do I Stop a Toilet From Running?

Fortunately, most of these repairs can easily be done by you with a few basic tools. If you’ve got a simple pair of pliers and access to a hardware store, that’s all you need. You aren’t required to replace the toilet and you won’t have to call a plumber either.

In order to make sure you fix your toilet problem, there’s some steps you should follow and some materials you should gather.

Tools You Need:
– Pliers
– Cutting pliers
– Rubber gloves
Materials You Need
– Replacement toilet fill valve
– Replacement toilet flapper
Project Step-by-Step
– To ensure you eliminate opportunities for a future running toilet, make sure you read through these steps before just attempting a single repair. There’s a few processes you should complete just to be safe.

Checking the Fill Tube

how to stop a running toilet


The fill tube is the small pipe that runs from the toilet fill valve into the overflow tube.

1. Remove your tank lid and locate the toilet fill tube.
2. If it’s disconnected, attach it properly.
3. Push the tube into the fill valve and make sure it’s about an inch above the top of the overflow tube.
4. Flush your toilet to make sure the water is heading down into the toilet overflow tube.

Adjusting the Fill Height

how to stop a running toilet

The float is easily adjustable for a DIY-er like yourself.

1. Look for the fill height mark that is on the back inside of the toilet tank and mark it onto the overflow
2. Flush the toilet and see if the tank water stops at the mark.
3. If it doesn’t, raise or lower the float to compensate.
4. Keep flushing after every adjustment in order to narrow down the right float level.

Adjusting the Flapper Chain

how to stop a running toilet

If your flapper chain is tangled or too short, you can adjust it yourself to try and fix the issue.

1. Locate your flapper chain and check for tangles.
2. Adjust the chain links so there’s only a little slack when you close the flapper.
3. Trim the excess chain and leave only an inch of extra. This reduces the chance of future tangling.
4. Replace the tank lid and test your toilet flush.
5. Make sure the chain rod doesn’t hit the tank lid when you flush. If it hits, adjust the chain again.

Replacing the Flapper

how to stop a running toilet

If the previous steps still leave your toilet running, it’s time to replace your flapper. Now, it might be a little more complicated. Because of the growth in toilet and flapper styles over the last decade, you might not be able to find your exact flapper, especially if you have an older toilet. Some products might be model or brand specific while some are universal flappers. If you can’t find exactly what you need, pick the closest one you can find. Just to be safe, pick up a universal flapper as well; it could save you the second store trip.

1. Turn off the water to your toilet. This comes from the water supply line that’s on your left side. Turn the handle that’s at the base of the line all the way right.
2. Flush to drain your toilet water from the tank.
3. Remove the tank lid.
4. Remove the old flapper. Take this to the store with you when you shop for a new one.
5. Install the new flapper.
6. Test the flapper to make sure it’s opening and closing correctly.
7. Make sure you test each flapper you install to make sure you’re getting one that seals properly.
8. Make sure you test each flapper you install to make sure you’re getting one that seals properly.
9. If you can’t find one that seals, you can replace the entire overflow tube and flapper assembly.
10. Adjust the flapper chain to meet the requirements of the new flapper.

Replacing the Fill Valve

how to stop a running toilet

Replacing the float valve is a simpler repair than you might think.

1. Turn off your water supply using the water supply line handle. This will be on the left side.
2. Flush your toilet to drain the water from the toilet tank.
3. Disconnect your water supply hose from the bottom of the tank. Make sure to place the loose end into something to catch any excess water.
4. Remove the fill valve by unscrewing the bolts at base of it. Take the old one to the store to purchase a new one.
5. Install your new float valve. The instructions may vary based on model so read the installation manual that comes with it.
6. Reconnect your water supply line.
7. Turn your water supply on to refill your toilet tank.

When to Call in a Professional

So, you’ve taken some time out of your day and labored through some home improvement toilet projects. Hopefully, the previous procedures will leave your running toilet finally in the right shape. If you powered through these steps like a champ, then congrats! You’ve learned a little more about some toilet maintenance. If you remember, you may be able to fix any future running toilets you might encounter.

If you’re one of the unlucky ones and nothing you do seems to fix it, that’s when you need to call a plumber. It’s never what anyone wants, shelling out some big bucks for a repairman, but it’s better than letting the running toilet run out of control. Repairing it now can prevent even costlier water bills and damage repairs. Plumbing costs are definitely worth it when you consider what could happen if you ignore your toilet problem.

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