The Ultimate Guide to Fixing a Running Toilet

By Brian on March 28, 2025

How to fix a running toilet efficiently can save you from soaring water bills and avoidable plumbing headaches. A running toilet not only wastes gallons of water but also signals hidden plumbing issues that require timely resolution.

Here’s a quick guide to address how to fix a running toilet:
1. Check the Flapper: Ensure it seals properly. Replace if worn out.
2. Inspect the Fill Valve: Adjust or replace it if water keeps filling the tank.
3. Examine the Chain: Ensure it isn’t too short or too long, affecting the flapper’s functionality.
4. Monitor Water Levels: Adjust the float to manage water levels effectively.

Tackling these common issues yourself could potentially save hundreds of gallons daily and reduce your water charges significantly.

In Northern California, where water efficiency is increasingly crucial, addressing a running toilet has both economic and environmental benefits. DIY repairs can be a fulfilling solution to familiar plumbing nuisances. However, if issues persist, professional plumbing services, like those offered by Go Pro Plumbing, ensure peace of mind with their expertise and outstanding customer service.

Diagnosing the Problem

When your toilet starts to run, it’s important to diagnose the issue quickly to prevent wasted water and rising bills. Here’s how you can identify what’s causing the problem:

Running Constantly

If your toilet is running non-stop, it could be due to a malfunctioning fill valve or a stuck flapper. A fill valve that keeps filling the tank could mean it’s misadjusted or faulty.

Check the overflow tube: If water spills into it, your fill valve is likely the culprit.
Observe the flapper: If it doesn’t seal properly, it might need cleaning or replacement.

Random Times

A toilet that runs intermittently, starting and stopping on its own, usually indicates a slow leak. This could be due to a worn-out flapper or a faulty flush valve.

Inspect the flapper: Look for any signs of wear or improper positioning.
Check for leaks: Use food coloring in the tank to see if it seeps into the bowl without flushing.

Water on the Floor

Water pooling around the base of the toilet can signal a few different issues:

External Leaks: If water is visible on the floor, it might be coming from the tank-to-bowl connection or the fill valve connection.
Wax Ring Issue: Water leaking between the toilet base and floor often means the wax ring needs replacement.

If you notice water stains or dampness around the toilet, it’s important to address these leaks promptly to prevent damage to your bathroom floor.

By identifying these common symptoms, you can address the problem effectively, ensuring your toilet runs efficiently and your water bills stay manageable.

How to Fix a Running Toilet

Fixing a running toilet can save you money and conserve water. Let’s break down how to tackle the most common culprits: the flapper and the fill valve.

Fixing the Flapper

The flapper is a rubber seal that controls the flow of water from the tank to the bowl. If your toilet runs constantly, it’s often due to flapper issues. Here’s how to fix it:

Inspect the Flapper: Open the tank and check if the flapper is sealing properly. If it’s worn out or dirty, it might not close completely.
Clean the Flapper: Mineral buildup can prevent a good seal. Clean the flapper gently with a cloth to remove any deposits.
Adjust the Chain Length: The chain connecting the flapper to the flush lever should have a little slack. If it’s too tight or too loose, adjust it. A chain that’s too short can pull the flapper up slightly, causing leaks. If it’s too long, it might get caught under the flapper.
Replace the Flapper: If cleaning and adjusting don’t help, it’s time for a new flapper. Turn off the water supply, flush the toilet to empty the tank, and unhook the old flapper. Install a new one by following the package instructions.

Adjusting or Replacing the Fill Valve

The fill valve controls the water level in the tank. If your toilet runs or fills slowly, the fill valve might need attention.

Adjust the Fill Valve: Check if the water level is too high. The water should be about 1/2 to 1 inch below the top of the overflow pipe. Adjust the fill valve to lower the water level if necessary. For float cup valves, you can turn the adjustment screw; for ball float valves, bend the float arm gently.
Check for Leaks: Lift the float arm while the tank is filling. If the water stops, the fill valve is working. If it doesn’t, you may need to replace it.
Replace the Fill Valve: If adjusting doesn’t solve the problem, replace the fill valve. Turn off the water supply, flush the toilet, and remove the remaining water with a sponge. Disconnect the water supply line, unscrew the fill valve locknut, and lift out the old valve. Install the new fill valve according to the instructions.
Test the New Valve: After installation, turn the water back on and test the new fill valve to ensure the water level is correct and the toilet isn’t running.

By addressing these common issues, you can ensure your toilet operates smoothly and efficiently, keeping your water bills in check.

Common Causes of a Running Toilet

Understanding the common causes of a running toilet can help you fix the problem swiftly and prevent further issues. Here are the three main culprits:

Leaking Flapper

The flapper is the rubber seal that controls the release of water from the tank to the bowl. A leaking flapper is the most common cause of a running toilet.

Worn or Damaged Flapper: Over time, the flapper can become warped or cracked, preventing a proper seal. This leads to continuous water flow from the tank to the bowl, causing the toilet to run.
Mineral Buildup: Hard water can cause mineral deposits to form on the flapper, preventing it from sealing correctly. Regular cleaning can help avoid this.

If you suspect a leaking flapper, inspect it for damage and replace it if necessary. You can find flapper replacements at any hardware store for less than $20, making it a cost-effective fix.

Damaged Float Ball

The float ball is part of the fill valve mechanism and helps regulate the water level in the tank.

Waterlogged Float: If the float ball becomes waterlogged, it won’t rise properly to shut off the water flow, causing the tank to overfill and run.
Improper Adjustment: A float ball set too high will cause the water to overflow into the overflow tube, leading to a running toilet. Adjusting the float ball can often solve this issue.

Regularly check the condition of the float ball and ensure it’s properly adjusted to avoid unnecessary water waste.

Broken Fill Tube

The fill tube is a small, flexible tube that directs water from the fill valve into the overflow tube to refill the bowl after a flush.

Disconnected or Broken Tube: If the fill tube is broken or disconnected, it can cause the toilet to run continuously as the bowl won’t refill correctly.
Incorrect Positioning: Ensure the fill tube is properly positioned and not submerged in the water, as this can create a siphoning effect, leading to a running toilet.

Inspect the fill tube regularly and replace it if you notice any damage. This simple fix can prevent your toilet from running and keep your water bills in check.

By identifying and addressing these common issues, you can maintain a smoothly functioning toilet and conserve water effectively.

Preventative Maintenance Tips

Keeping your toilet in good shape can save you time, money, and water. Here are some easy preventative maintenance tips to help you avoid a running toilet.

Regular Inspections

Frequent checks are key to catching issues early. Every few months, lift the tank lid and look inside. Make sure all parts are working as they should. Check for signs of wear or damage, like cracks or leaks.

Inspect the Flapper: Look for warping or mineral buildup. A simple cleaning can extend its life.
Check the Fill Valve: Ensure the fill valve shuts off properly when the tank is full. Adjust it if necessary to prevent overflow.

A quick inspection can prevent small problems from becoming big repairs.

Cleaning Sediment

Sediment buildup can affect your toilet’s performance. Minerals from hard water can clog parts and cause leaks.

Flush the Tank: Turn off the water supply, flush the toilet to empty the tank, and scrub away any sediment with a brush.
Clean the Fill Valve: Sediment can clog the valve, causing it to malfunction. Clean it regularly to ensure smooth operation.

Cleaning sediment keeps your toilet running efficiently and prevents unexpected issues.

Replacing Worn Parts

Over time, parts like the flapper and fill valve wear out. Replacing them before they fail can prevent a running toilet.

Replace the Flapper: If it looks worn or damaged, swap it out. A new flapper is inexpensive and easy to install.
Upgrade the Fill Valve: If your fill valve is old or not working well, consider replacing it. Newer models are more efficient and can save water.

By keeping parts up to date, you can avoid leaks and keep your toilet in top condition.

These simple steps can help you maintain your toilet and reduce water waste. Next, we’ll address some frequently asked questions about running toilets.

Frequently Asked Questions about Running Toilets

How do I stop my toilet from trickling water?

A toilet that trickles water can be annoying and costly due to wasted water. Here’s how to tackle it:

Check the Shut-Off Valve: Ensure the shut-off valve is fully open. If it’s partially closed, it might restrict water flow and cause trickling.
Replace the Flapper: A leaking flapper is often the culprit. Over time, flappers can warp or crack, preventing a proper seal. If water is trickling, inspect the flapper. If it’s damaged, replace it with a new one. This simple swap can stop the trickling and save you gallons of water daily.

What is the most common cause of a running toilet?

The most common cause of a running toilet is a leaking flapper. When the flapper doesn’t seal properly, water leaks from the tank into the bowl, causing the toilet to run continuously.

Another frequent issue is a damaged float ball. If the float ball is cracked or not set correctly, it may not rise enough to signal the fill valve to shut off. Adjust or replace the float ball to fix this.

How do I fix a toilet that keeps stopping up?

A toilet that frequently stops up is frustrating, but there are straightforward fixes:

Use a Plunger: Sometimes, a simple plunger can clear minor blockages. Ensure you have a good seal around the drain and push firmly to dislodge the clog.
Blockage Removal: If plunging doesn’t work, there could be a more significant blockage further down the pipe. Use a toilet auger to reach deeper and remove the obstruction.

Regular maintenance and prompt attention to these issues can keep your toilet running smoothly and efficiently.

Conclusion

Fixing a running toilet doesn’t have to be a daunting task. By understanding the common causes and solutions, you can save water, reduce your bills, and avoid the constant annoyance of a running toilet. But sometimes, the problem might be more complex, or you simply might not have the time or tools to fix it yourself. That’s where we come in.

At Go Pro Plumbing, we pride ourselves on providing exceptional customer service and same-day service to ensure your plumbing issues are resolved quickly and efficiently. Whether you’re dealing with a running toilet, a severe clog, or any other plumbing emergency, our experienced and certified team is ready to help.

Our commitment to outstanding customer service means we’re here to answer your questions, address your concerns, and provide transparent pricing without any hidden fees. We understand the urgency of plumbing problems, which is why we guarantee fast and effective solutions.

If you’re in Rancho Cordova, Sacramento, or anywhere in Northern California, don’t let a running toilet disrupt your day. Contact us and experience the Go Pro Plumbing difference. We’re here to help you get your plumbing back in top shape, saving you time, stress, and money.