Is Your Toilet Running? How to Fix a Running Toilet.

For this toilet repair, you’ll need: Pliers and Screw Driver

A constant noise coming from the toilet means you have a toilet running, it’s not getting filled with rough water to stop. A toilet repair is needed.  A running toilet can cost a lot in water bills and it’s noisy.

Do it yourself and avoid calling a plumber for a toilet repair, first you have to diagnose the problem

Fix Your Toilet Running Problem

overflow tube prevents a toilet running problem
Overflow Tube
  1. Overflow tube, if water is spilling over the top into the tube, the water level is set to high and the toilet doesn’t know when to stop.

A toilet running never knows it’s full.

You can adjust the water level by bending the float arm, or adjusting the screw on top of the fill valve.

There’s always a screw at the top of the fill valve for adjusting the water level.  You may need to do a few test flushes to find the right adjustment for the screw for this toilet repair.

  1. Flapper.  Check the flapper, if it is bad then water is constantly leaking down into the bowl and the fill valve never stops trying to fill the tank.  

Look at the chain that leads to the flapper, if there is not enough slack in the chain, it might be holding the flapper open causing the toilet running problem. If this is the case, give the chain more slack by moving the hook up the chain a link or two.

If the chain isn’t the problem. push down on the flapper and wait, if the toilet stops running then you know the flapper is bad.  A toilet repair is needed to fix your running toilet. The flapper should be replaced. To remove the flapper, simply slip it off or unsnap it and take it to the hardware store to purchase an exact match and replace it like you took it off.

toilet flapper prevent toilet running
Toilet Flapper


  1. Toilet Fill Valve.  If there wasn’t any problems with the water level or the flapper then the fill valve has to be the toilet running problem.  It’s
    fill valve fixes a toilet running problem
    Toilet Fill Valve

    possible to repair it, but it’s easier to replace it. A new toilet fill valve costs less than $15 dollars. On almost all toilets, the fill valves are interchangeable.  You can replace your fill valve with a newer style. Before you remove the fill valve, shut off the water at the wall and flush the toilet. There will still be about an inch of water at the bottom of the tank.  Use a bucket to drain the water as you disconnect the water supply on the underside of the toilet.

On the underside of the toilet:

  • Unscrew the nut that holds the fill valve in place
  • Remove the fill valve and replace
  • Reverse your steps to install the new valve

You will have to read the directions to set up the new valve for your particular toilet.  And after everything is reassembled, you will still need to set the water level by the adjustment screw at the top of the fill valve.


One of these suggestions will fix your toilet running problem and you will save at least $100 that you would spend calling a plumber for toilet repair. Thanks for coming to the best plumbing tips website