why your toilet is running

What To Do When Your Toilet Keeps Running

Plumbing issues can be incredibly frustrating. Often they come with no obvious warnings and sometimes, hefty repair bills. Toilet problems are especially common.

One of the most common toilet issues is a running toilet. What is a running toilet, you may ask? A running toilet is constantly running even when not flushed. Several issues can cause a running toilet, so the reason for the running toilet may not even be obvious. However, a running toilet is an issue that should be solved quickly. If left to run, your water bills may increase due to wasted water.

So what are you supposed to do when your toilet keeps running?

Preparation For Fixing A Running Toilet

We recommend gathering all the necessary tools. You will need wire cutters, a permanent marker, a flat-head screwdriver, and a Phillips screwdriver. Next, you’ll need to open the toilet tank by lifting the cover off. Then you can narrow down possible causes that can be fixed DIY-style.

Figure Out Why Your Toilet Is Running

Fill Tube

Observe the tank for a vertical tube. This is known as the overflow tube. If the tank is too full, water pours into the overflow tube. This keeps your toilet water from flooding out of the tank. On some toilets, there will be a small tube that connects the fill valve to the overflow tube. This is your fill tube. If you have a fill tube, make sure that it’s connected to the fill valve and flowing into the overflow tube. Then, flush to check if it’s working.


The next item that you should check is the flapper. Pick it up and check if it is worn out around the outside rim. If so, water is likely pouring in through the worn-out parts. If this is the case, you can remove it and replace it with another flapper. Universal flappers are often available at most hardware and repair shops. 

The Flapper Chain

Do you see a chain connected to the flapper? That’s called the flapper chain. Sometimes if the flapper chain is too long, the chain might hang too low and become caught underneath the flapper. This would cause a flapper to not fully close and let water leak through. If this appears to be the case, you can use your wire cutters to carefully trim the chain. You don’t want to trim it too much. We recommend starting with 1-2 chain links and then checking to see if there’s still too much slack. You’ll want some slack, but not enough to get caught under the flapper.

Overflow Tube & Float

If your water level is too high, water may start to constantly flow into the overflow tube. This can result in your toilet running.

That being said, this isn’t too difficult to fix. Generally, you just need to adjust the float. When everything is working properly, the float will rise with the level of water to a certain point. At that point, the water will stop rising. When your float is rising too high, you’ll encounter the water pouring into the overflow tube, causing your toilet to run.

The water should only rise to about ½ to 1 inch below the top of the overflow tube. You can mark that point off with a permanent marker and check at the end to see if you have the water stopping at the correct point.

There are a few different types of floats you’ll encounter.

Modern Floats

Modern floats can be adjusted by locating the spring clip or adjustment screw. If it’s a screw, just use your Phillips screwdriver and move it a tiny bit to the left. This will lower the float into the basin.

Ballcock Floats

On older toilets, you may encounter what’s known as a ballcock float or a float ball. The floating part looks like a sphere on the end of a metal rod, known as the float arm. If your toilet is overflowing, you’ll want the float ball to go deeper into the tank. There are two ways you can adjust this. First, you can use your screwdriver to adjust the screw at the top of the arm. By tightening it a little, you’ll stop the arm from rising too high. Or, if you can’t adjust the screw, you can carefully bend the float arm to angle the float ball downwards.

Call A Trusted Plumber

If you’ve tried all these troubleshooting steps and your toilet is still running, you may need to call a plumber. If you are looking for a trustworthy, friendly plumber in Honolulu, contact 535 Plumbing! We’re a family-owned and operated plumbing business that loves to go above and beyond for our customers. Contact us at (808) 300-0535.