You probably remember the juvenile joke: “Is your toilet running? Yes. Go catch it.” While that may bring you back to your youth, a constantly running toilet isn’t a laughing matter – it will increase your water bill and could also lead to more significant damage if not checked. Learning how to fix a running toilet, though, can be a relatively easy and inexpensive repair, and you may be able to do it yourself. It will probably cost you no more than $25 and might not cost anything depending on the problem. It will take less than an hour, providing you have the right materials.

Tools and other items you may need include pliers, an adjustable wrench, wire cutters, vinegar or mineral spirits, and a toothbrush. Depending on the problem, you may need a new flapper, a new float, or a new fill valve. 

Identifying and Fixing the Problem

Three main things can go wrong with a toilet. Here is how to identify and then fix each one.

Bad flapper

This is the most common problem. This is how to handle it.

  1. Turn off the water to the toilet, flush it, remove the lid, and inspect the flapper.
  2. If it is not forming a tight seal because the chain attaching it to the flush lever is too short or long, adjust the chain. Use the wire cutters, if necessary, to shorten the chain.
  3. If there is a mineral buildup, remove the flapper and put it in the mineral spirits or vinegar for half an hour. Scrub it with the toothbrush and replace it.
  4. If the flapper is warped or deteriorated, you’ll need a new one. Remove the flapper and take it to the hardware store to make sure you are getting the right replacement. Install the new flapper according to the instructions.


If your ball float or cup float is not adjusted properly, it can lead to high water levels which will cause running.

  1. Check the overflow tube. If it is taking on water, your water level is too high.
  2. Using pliers, turn the float’s control screw counterclockwise until the water level is at least an inch below the overflow tube.

Toilet fill valve

This is the most complex problem, and you may elect to have a professional plumber handle this.

  1. Shut off the water to the toilet, flush it, and using the pliers or adjustable wrench, disconnect the service line.
  2. Dry the tank.
  3. Use the wrench to remove the old fill valve.
  4. Bring it to the hardware store to make sure you have the right replacement.
  5. Install the new valve following the directions.
  6. Flush the toilet to make sure it is working.

Contact Ravinia Plumbing, Sewer, Heating & Electric for Your Home’s Plumbing Needs

If you’re uncomfortable with performing even minor plumbing repairs such as fixing a running toilet on your own, contact the professional plumbers at Ravinia Plumbing today. We’ve been in business since 1928, and we’ve made a name for ourselves as one of the most trusted and reliable plumbing companies in Chicagoland. Contact Ravinia Plumbing today to schedule an appointment.