4 Reasons Why Your Toilet Keeps Running and How to Fix it?

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A running toilet is one of those irritating things that you never think about… until it actually happens. 

You may not have paid too much attention to this, but the flushing action on the average toilet takes anywhere from 10 to 15 seconds or less. 

After the toilet has been drained of all the water, it takes about another 45 to 90 seconds to refill — any longer than that and something’s definitely up with the toilet. 

But what do you do if your toilet keeps running? 

Well, you definitely don’t want to ignore this problem. A running toilet can easily waste hundreds of gallons of water daily, which will surely hike up your water bill. 

Here are the top reasons why your toilet may keep running, and here’s how to fix them.

Why Does My Toilet Keep Running?

You may not immediately notice that your toilet is still running — sometimes, unfortunately, all night. 

I’ve noticed when dealing with this issue that the culprit usually comes down to four main components: the flapper, the float, the chain, and the refill tube.

The Toilet Flapper Is Worn or Cracked

Nine times out of ten, if the toilet is running the flapper is the issue. 

It’s also worth noting that the more people that are using the toilet, the faster this and other components are likely to become worn. 

Because of this, I personally believe that you should change your toilet flapper every year to prevent this type of issue altogether.

When your toilet flushes, the flapper lifts to allow the water to drain from the tank, before it closes so that fresh water can refill (via the fill valve) it and the bowl. 

However, over time, these flappers can harden and crack. 

As a result, the flapper will not fit over the valve correctly and water will seep into the tank, causing it to run nonstop. If you discover that this is the issue, turn off the water supply with the valve behind the toilet as soon as possible. 

There Is an Issue With the Flapper Chain

Here’s another issue that can present itself with the flapper — the chain. 

Sometimes the chain on the flapper can be either too long or too short, causing issues with its ability to connect to the field valve. 

If the chain is too short, the flapper won’t be able to cover the valve completely. If the chain is too long, it won’t lift the flapper high enough to allow water to drain out of a tank. 

Though these chain links are typically universal, you may run into issues if you have a high-end or customized toilet, or if you happen to purchase a toilet repair kit that has an adjustable chain. 

Issues With the Float Arm or Tank Float Ball

If the float ball or float arm starts to malfunction, this can also cause the toilet tank to run continuously. 

Remember that the float arm is responsible for controlling the water level inside the tank, so when it’s set too low it will produce a rather weak toilet flush. 

If the arm is set too high, too much water will begin spilling inside the overflow tube. As a result, the fill valve simply will not shut off — resulting in a continuously running toilet. 

The float ball, on the other hand, is connected to the float arm, and it rises as the tank fills with water after a flush.

Over time, these float balls can crack, which’ll cause them to lose their buoyancy. If that happens, they’ll begin to fill up with water. Then, the big show is over. 

The water will continuously pour into the overflow tube, which feeds the water into the toilet bowl. And as a result — yes, you guessed it — the toilet will flush continuously.

The Refill Tube Is Malfunctioning or Needs to Be Adjusted

And, of course, there’s the issue with the refill tube, which is located next to the fill valve. 

The refill tube (aka the “overflow pipe”) can also be a bit of a trouble maker, as it’ll continuously pump water into the tank and toilet bowl if it’s not adjusted correctly. You’ll usually see this happen when it’s too long or is positioned incorrectly inside the overflow tube. 

If you’re not familiar with the internal components of a toilet tank, this issue may be harder to initially spot. (Note: Always check to see how much water actually makes it inside of the overflow tube).

How to Fix a Running Toilet

After you’ve done a bit of detective work to determine why your toilet keeps running, you’re well on your way to repairing it. 

You’ll find that a running toilet tank is typically an easy fix, and it usually just involves adjusting or replacing one of the components in the tank.

Lower the Float Arm or Replace the Ball

If you find that the float arm is causing the issue with the running toilet, start by looking for a small screw attached to it that you can tighten or loosen. In some cases, it may be a clip instead. 

If it has a screw, turn it to the left to loosen up the arm and then manually lower it. And if it has a clip, simply push it down so that the arm can be lowered. 

If the issue is with a defective flow ball, you’ll need to purchase a new one. 

This fix is so easy that a kid could do it… not that you’d want a child tinkering with your toilet tank. To replace the ball, simply remove the old one by sliding it back from the lever. Then slide the new ball on. 

In some float ball kits, you may need to replace the entire valve assembly instead of just the ball. 

Replace the Toilet Flapper

Here is another straightforward fix. 

In many cases, a flapper will come with a fill valve repair kit. However, you can also purchase this component individually at a local home improvements store, such as Lowe’s or Home Depot. Heck, you may even be able to find this common item at a Walgreens or Walmart. 

Inside your toilet, the flapper is usually connected to the chain by a couple of loops. Simply unhook the loops and attach the new flapper to replace it. 

After doing so, be sure to give the toilet a flush to check its filling capabilities. Don’t be fooled by the flapper simply laying over the ball — be sure that the water stops flowing completely and that the tank eventually fills back up. If it does, you’re golden!

Fix the Flapper’s Chain

Speaking of chains, if the chain is too short or too long, you’ll need to adjust it so that the flapper can fit over the valve properly. But don’t worry, replacing it is as easy as 1-2-3. All you need is a pair of wire cutters or pliers. 

If the chain is too long, it’s best to cut only one or two links at once to avoid making it too short. After you’ve adjusted the chain, lower the flapper and flush the toilet. 

If the flapper closes completely over the valve, you’re good to go. 

Unfortunately, if the chain is too short, you’ll have to replace the entire assembly. 

Shorten the Toilet’s Refill Tube

Lastly, you have the refill tube. 

You can shorten the refill tube using one of two ways. You can clamp it off closer to the overflow opening, so it pours right into the overflow tube. Or, you can cut it with a pair of shears or a utility knife. 

If you only need to shorten it by an inch or less, it may be easier to simply re-clamp it. 

To do this, loosen up the clamp on the end of it, and move it toward the top of the tube. Then, flush the toilet to check for any leaks into it. After you’re done placing the overflow tube, flush the toilet once again to ensure that the water flows into it well. 

If not, you’ll need to adjust as necessary or the toilet will keep running. It may take a few minutes of fumbling with it to get it back in position, but when it is, the water should fill the tank up rather quickly. 

It’s also worth noting that the refill tube will sometimes come in a complete kit that includes the flush valve and other components.

The Bottom Line 

So, what’s the bottom line? When a toilet keeps running, it can take a bit of troubleshooting to determine and then fix the cause. However, it’s typically something that you can do yourself. 

This means you can save the hundreds of dollars that you’d typically have to pay a plumber to do this for you. 

However, if you find that you can’t troubleshoot the problem with your running toilet, and none of these scenarios seem to fit the bill, it may be time to call your local plumber to have them check out your porcelain throne.

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