How to Fix a Running Toilet

How to Fix a Running Toilet

How to Fix a Running Toilet: Tips from Tony's Drain and Sewer Cleaning

A running toilet can be a significant problem in a household, causing not only irritation but also high water bills. It's a leaking toilet that can waste up to 200 gallons of water every day. To help you stop the toilet from running and save water, Tony's Drain and Sewer Cleaning provides you with the following tips.

Step 1 - Check the Water Level

The first thing to do is to check the water level to determine if the toilet has a leak and how much water it is leaking. You can check for leaks by opening the toilet tank and using a pencil to draw a line at the water level. Turn off the water supply valve beneath the toilet and come back in an hour to see if the water level has dropped below your line.

Alternatively, you can squirt five or six drops of brightly colored food coloring into the tank and wait for 30 minutes to an hour. If the water in the bowl has turned the color of the food coloring, you have a leak.

Step 2 - Check the Flapper
The flapper valve is the rubber piece that flips open when the flush handle is used. It slowly lowers back down over the flush valve to close off the flow of water into the bowl. If the flapper gets stiff and brittle over time, it will no longer provide a good seal against the mouth of the flush valve. In most cases, replacing the flapper is how to stop a toilet from running.

It's important to inspect the chain that connects the flapper to the flush handle arm. If it's too long, the chain may fall between the flapper and fill valve, allowing water to constantly drain into the bowl. If the chain is too short, it may prevent the flapper from closing fully and prevent the flapper from making a good seal when closed.

Step 3 - Check the Fill Valve and Float Ball
The fill valve is the tall piece that connects to the toilet's water supply line. You'll notice that the top part of the fill valve is connected to the float arm, and it has a float adjustment screw at the very top. When the toilet is running, lift the float ball and see if the running stops. Then, look to see if the water level in the tank is high enough that it is allowing water to spill into the overflow tube part of the flush valve. If so, this is probably the main source of your leak and why your toilet is running.

Adjust the float adjust screw and adjust the float to control the water level. Ideally, the water level in the tank should be an inch or two below the top of the overflow tube. Check the fill valve to see if water is leaking out of the top. If so, it's time to replace it.

Step 4: Check the Flush Valve
If the flush valve needs to be replaced, it's important to turn off the water supply to the toilet and drain the water from the tank before beginning the replacement process. This can be done by shutting off the water valve located near the base of the toilet and then flushing the toilet to drain the water. A towel can be used to soak up any remaining water in the tank.

Once the tank is empty, remove the old flush valve by unscrewing it from the base of the tank. Install the new flush valve according to the manufacturer's instructions, making sure to tighten it securely to prevent leaks. Once the new flush valve is installed, turn the water supply back on and test the toilet to make sure it is no longer running.

A running toilet can be a frustrating and costly problem for homeowners, but with the right tools and knowledge, it can be easily fixed. By following the steps outlined in this guide and regularly maintaining your toilet's components, you can prevent future leaks and keep your toilet running efficiently.


Tony had been dealing with a running toilet for weeks. Despite his attempts to jiggle the handle and adjust the fill valve, the toilet continued to run and waste water. He knew he needed to do something before his water bill skyrocketed, so he decided to take matters into his own hands and try to fix the problem himself.

He began by checking the water level in the tank and discovered that it was constantly dropping. He used a pencil to draw a line at the water level and turned off the water supply valve beneath the toilet. After an hour, he returned to check the water level and found that it had indeed dropped below his line, confirming that there was a leak.

Next, he squirted a few drops of bright red food coloring into the tank and waited to see if the water in the bowl would turn red. Sure enough, the water turned red, indicating that there was a leak somewhere in the system.

Tony then checked the flapper valve and found that it was stiff and brittle. He replaced the flapper and adjusted the chain to ensure that it was the correct length. He then checked the fill valve and float ball, adjusting them to control the water level in the tank.

Despite his best efforts, however, the toilet was still running. He proceeded to check the flush valve and found that it was indeed leaking around the mouth where the flapper was supposed to make a seal. He tried using emery cloth to smooth out any rough areas, but it didn't work. Ultimately, he had to replace the flush valve entirely.

After turning off the water supply and draining the tank, Tony successfully replaced the flush valve and turned the water supply back on. To his relief, the toilet was no longer running and he could finally put the frustrating problem behind him.

By following the steps outlined in this guide and taking the time to maintain his toilet's components, Tony was able to save money on his water bill and prevent future leak. 

How to Fix a Running Toilet Written by Tony's Drain & Sewer Cleaning

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