How to Troubleshoot & Fix a Running Toilet

Your home’s toilets are the workhorses of its plumbing system. Despite constant use, most toilets will work flawlessly for years. However, you may encounter a few common toilet issues from time to time. One is a toilet that won’t stop running. There are a few different causes for the problem. It helps to understand them, so you know what to expect when you hire a plumber for repairs. With that in mind, here’s what you need to know about troubleshooting and repairing a constantly running toilet.

Diagnosing the Cause of the Problem

Before any repairs can occur, it’s first necessary to isolate the cause of your toilet’s problem. Doing that requires an examination of your toilet’s specific symptoms. If your toilet randomly flushes and refills, you’re experiencing ghost flushing. It almost always results from a problem with the flapper at the bottom of your toilet tank. Occasionally, however, it can happen due to an internal leak inside your toilet.

If you hear a near-constant flow of water but your toilet doesn’t flush on its own, you likely have a fill valve or float issue. What you’re hearing is the valve letting water into the tank, with the excess water going straight down the drain via the overflow tube.

If you hear your toilet constantly running and you see water on the floor surrounding it, it has an external leak. The three most common external leak locations are at the fill valve’s base, the toilet’s wax ring, or the tank-to-bowl junction.

In any of these cases, the first thing to do, when your toilet won’t stop running, is to turn off its water supply. Every toilet has a nearby shutoff valve, where its water supply line connects to your plumbing. To turn it off, rotate the valve clockwise until it doesn’t turn any further. This is an essential step to prevent flooding while the toilet undergoes repairs.

The next step is flushing the toilet. That will remove most of the water remaining in the tank. Then, after removing the tank lid, it’s possible to visually inspect the flushing mechanism for obvious problems.

Solving Flapper Problems

In many cases, issues with a toilet’s flapper result from some mundane causes. One issue is with the chain connecting the flapper to the flush arm. If the chain becomes tangled, it may be too short to allow the flapper to fall into position. That would lead to water constantly draining from the tank. In that case, untangling the chain should solve the problem.

The other common flapper issue is sediment or scale buildup on the flapper or tank drain. That can prevent a tight seal between the two, which allows water to escape the tank. Using a soft brush to scrub the flapper and drain opening may fix the problem.

The flapper may need replacement if the previous two solutions don’t work. The good news is that replacement flappers aren’t expensive, and the work involved is minimal. Most toilet flappers attach to two posts protruding from the tank’s overflow tube. It’s a simple matter to pull the existing flapper off those posts and put a new one in its place. Most homeowners are comfortable doing this, but our plumbers are happy to help if you’re not.

Solving Fill Valve Problems

If your toilet has a fill valve issue, a few approaches are available to repair it. The first step is to ensure the valve’s float moves freely. If it doesn’t, the entire valve may need replacement. If it does move freely but the valve doesn’t turn off at the high-water float position, an adjustment may fix it. For valves with a metal float arm, slightly bending the arm down should apply more pressure to close the valve. A screw-driven height adjustment serves the same purpose for valves with integrated floats.

If the valve doesn’t close, regardless of the float position, the valve may need a new seal installed. When a fill valve seal fails, you may also see water coming from the top of the valve itself. A fill valve seal looks like a small rubber disc. It sits inside the valve and blocks water flow in response to the pressure exerted by the float arm. Replacing the seal in a typical fill valve requires the removal of the valve cap and valve assembly. Then, pulling the old seal out and inserting the new one is possible. Afterward, the valve assembly and cap should be reinstalled to restore the toilet to working order.

If you have a leak coming from the base of the fill valve, replacing the whole valve assembly may be necessary. Fill valve problems are slightly more complicated than flapper issues, so many homeowners call us for these issues.

Solving External Leaks

If your toilet leaks somewhere besides the base of the fill valve, repairs may or may not be possible. Leaks from the base of your toilet where it meets the floor are, sometimes, the result of a damaged wax ring. That’s the component that seals the toilet against the drain opening in your bathroom floor. 

If the leak appears to come from the tank-to-bowl junction, it can result from two different issues. Uneven bolt tightening can lead to leaks at the tank-to-bowl junction. Typically, a toilet tank has two bolts holding it in place on either side of the bowl. They must apply even pressure to the gasket between the two parts to prevent leaks. If the bolts aren’t the issue, the gasket may need replacement. Replacing the gasket requires removing and replacing the tank, which is a job for a plumber.

Unfortunately, some external leaks stem from cracks in your toilet’s porcelain. In those situations, repair is impossible, and we will need to replace the toilet.

Why You Shouldn’t DIY Most Toilet Repairs

While some of the repairs mentioned here may seem easy, there are consequences to making mistakes while performing them. At a minimum, you might cause a small leak. At worst, you could damage your toilet’s porcelain, forcing you to replace it. It’s a good idea to let a qualified plumber handle toilet repairs to avoid any issues. You’ll get faster results with no risk of any damage to your toilet. Plus, having a professional inspect your toilet could uncover underlying issues with your plumbing. That gives you a chance to take corrective action before additional problems occur.

Your Local Toilet Repair Specialists

If you own a home in Weatherford, TX, with a malfunctioning toilet, Lightfoot Plumbing, Heating, Air & Electrical can help. We’ve served the plumbing needs of local homeowners since 1984. In that time, we’ve built a plumbing team that’s among the best in the business. Our plumbers are all highly trained, background checked, and wear our uniform proudly. Their exemplary work has earned us countless five-star customer reviews.

We’re also Better Business Bureau accredited with an A+ rating. We offer 24/7 emergency services for all plumbing problems that can’t wait. We also provide expert installation and maintenance for plumbing fixtures and water/sewer lines. If you need help with a toilet that won’t stop running in Weatherford, call Lightfoot Plumbing, Heating, Air & Electrical today!