Home » How Tos & Tips » How to Stop a Toilet from Running

How Tos & Tips

How to Stop a Toilet from Running

Audra Kincart
December 19, 2023

How to Stop a Toilet from Running

A constantly running toilet is not only a nuisance but can also increase your water bill. The good news is many reasons behind a running toilet are easily fixable through simple do-it-yourself solutions. More specifically, you can expect to resolve the issue in no more than an hour, below $50, and with an intermediate skill level. In this guide, we’ll walk you through the troubleshooting process. So, let’s dive in and put an end to that pesky toilet sound!

Why is My Toilet Running?

Before troubleshooting, let’s cover the mechanics of how a toilet works. Remove the lid from your toilet tank and follow the guide below:

Fill Valve Tube: Water enters the tank through a tube known as the fill valve tube. This component regulates the water level in the tank.
Flapper Functionality: The flow of water in the tank is controlled by a flapper—a sizable gasket positioned at the tank’s bottom. It serves as a barrier, preventing water from entering the bowl.
Float Rod and Buoy: As the tank fills, a float rod, accompanied by a buoy, rises with the water level. The fill valve stops the water flow when the float rod reaches the determined water level.
Flush Mechanism: Once the tank is adequately filled, flushing the toilet engages a chain connected to a flush valve flapper. This releases water from the tank into the toilet bowl.
Drainage Process: The water in the bowl is then directed through a trap and into the main drain.
Tank Refill: The water continues to flow until the tank is empty. Subsequently, the flapper returns to its original position, creating a watertight seal between the tank and the bowl.

Now let’s dive into some of the more common causes behind a running toilet:

Overflow Tube Issues: One potential culprit is the overflow tube, designed to prevent the toilet tank from overflowing.

Flush Valve Malfunction: Another common issue is the flush valve, which is responsible for releasing water into the tank during a flush. This is the most common cause of a running toilet, but the good news is that it’s also one of the simplest problems to fix.
Faulty Fill Valve: Last but not least, a running toilet can be caused by a malfunctioning fill valve. More on this later.

Tools and Materials

To tackle the issue, make sure to have the following tools:

Channel locks
Screwdriver
Bucket
Towel, cloth, or sponge
Cutting pliers
Rubber gloves

Additionally, gather the necessary materials

Replacement flush valve chain (optional)
Replacement fill valve (optional)
Toilet flapper (optional)

How to Fix a Running Toilet

Now you have a grasp of how your toilet functions, let’s dive into fixing the problem.

1. Fill Tube

If water is continuously running, the problem likely lies within the tank. Begin by examining the fill tube for any issues. This flexible tube extends from the fill valve on the left side of the tank to the overflow tube on the right side, which prevents water overflow and floor spills.

Check if the fill tube is securely attached to the fill valve. If loose, firmly push the tube onto the fill valve.
Make sure the fill tube perches one inch above the rim of the overflow tube.
Confirm the fill tube doesn’t extend into the overflow tube. If it does, trim the tube accordingly.
Flush the toilet and watch the water stream to make sure the water flows down the overflow tube without interruptions.

2. Float

The next part to examine is the float—a round-shaped plastic part situated on the fill valve, responsible for controlling the water level. A misaligned float can lead to continuous water flow or a weak flush, making it the next part to troubleshoot.

If possible, unscrew the float and give it a shake. Replace the float if you hear water inside; otherwise, reattach it securely.
Measure one inch down the overflow tube and make a mark. This mark represents the maximum fill level. Ideally, the water should stop at least one inch below this point.
Flush the toilet and watch where the water reaches.
Locate the screw that attaches the float rod to the fill cup or the clip along a rod (depending on your toilet model) and adjust accordingly. Note your toilet will have either the screw option or the rod option, but not both.
Flush the toilet after each adjustment.
Continue adjusting until the water shuts off at the correct level.

3. Handle

If the fill tube and water level are fine, check the toilet handle. If you have to hold the lever down to complete a flush or if the water cycles on or off, this is likely your issue.

Check the chain length. The toilet handle is connected to a chain inside the tank, leading to a flapper. If the chain is too short, the flapper won’t seal; if too long, the flapper might stay open, keeping the tank refilling.
Adjust the chain linkage, leaving a slight bit of slack (approximately one inch) when the flapper is closed. Remove links or cut the chain to the desired length.
If the chain is too short to adjust, purchase a replacement flush valve chain.
Replace the toilet lid. If the flush rod strikes the lid when you press the handle, gently bend the lever and readjust the chain.

4. Flapper

If the previous steps haven’t resolved the issue and your toilet is still running, there’s a good chance that the flapper is worn out. The flapper serves as a seal, allowing water in and out as you use the handle. When this malfunctions, it can lead to water leakage from the tank.

Turn off the water supply. Locate the shut-off valve near the base of the toilet and turn it clockwise to shut off the water supply.
Drain the toilet tank by flushing the toilet to drain as much water as possible.
Remove the remaining water using a towel or sponge.
Inspect the flapper. If it’s dirty but otherwise in good condition, clean it with a water and vinegar solution. Proceed to step 8.
If the flapper is damaged, remove it and continue to the next step.
Purchase a replacement flapper. Visit a home improvement store and look for the same flapper or a universal flapper. If uncertain, consider buying multiple options to save yourself additional trips. Flappers are relatively inexpensive.
Install the new flapper by following the instructions provided.
Turn the water supply back on.
Flush the toilet. If the issue persists, try a different flapper.

5. Fill Valve

If, after all of this you still have toilet running issues, you’ll have to replace the flush valve.

Order a compatible flush valve assembly online or purchase one from a home improvement store. Make sure the new overflow tube is tall enough for your toilet tank.
Shut off the water supply.
Drain the water by flushing the toilet.
Using a cloth, towel, or sponge, soak up any remaining water in the tank.
Use channel locks to disconnect the water supply.

Remove the Old Flush Valve:

Disconnect the flapper.
Remove the tank-to-bowl bolts and lift the tank off the toilet to access the toilet-to-bowl gasket.
Loosen the flush valve nut and remove the old flush valve assembly. Place it in a bucket to capture any extra water.

Install the New Flush Valve:

Install the new flush valve, ensuring it is properly positioned.
Tighten the flush valve nuts to secure the new flush valve.
Replace the tank-to-bowl gasket.
Put the tank back into position.
Secure the tank-to-bowl bolts.
Reconnect the water supply.
Check for leaks. Allow the tank to fill up and check for any leaks at the base of the tank.

If water continues to run after the tank is full, the tank-to-bowl gasket or the flapper may be improperly installed.

Preventing Toilet Issues

Now you’ve resolved your toilet issues, follow these tips from seasoned Taskers to prevent future problems.

Regular maintenance: Regular maintenance helps identify and address issues before they escalate. Regularly clean your toilet and look for any signs of leaks or wear and tear.
Mindful flushing: Avoid flushing non-flushable items such as feminine products, paper towels, and wet wipes. These can lead to clogs or damage to the flushing mechanism.
Replace old components: If your toilet is aging, consider proactively replacing old components before they cause issues. It’s better to replace them preventatively rather than wait for a failure.
Household education: Make sure everyone in your household knows what should and shouldn’t be flushed.
Install a water softener: Consider installing a water softener if you live in an area with hard water. Hard water can lead to mineral deposits in the toilet, affecting its efficiency over time. A water softener can help reduce mineral buildup, extending the lifespan of your toilet and minimizing the chances of clogs.

When to Get Help?

If, despite your efforts, you continue to experience persistent toilet running issues, it might be the right time to seek assistance. Additionally, if you feel uncomfortable dealing with toilet parts or simply want to guarantee a job done right, consider reaching out to a skilled Tasker to address not only your toilet concerns but also any other Plumbing needs you may have. A professional can provide expertise and ensure that the necessary repairs or replacements are handled with precision and efficiency.