Plumbing 101: How to Fix a Running Toilet

Mac Plumbing would love for you to call us if your toilet won’t stop running, but there are some things you can try yourself until we get there 

A running toilet can mean excess water usage, higher water bills, and possible water damage if left unchecked. Plus the sound of a running toilet can be irritating. If you’ve decided to try a DIY project before calling a plumber, Mac has some tips on where to begin.

Do You Know the Key Parts of Your Toilet?

  • Toilet Fill Valve
    • This is the element responsible for refilling the tank after every flush.
  • Toilet Flapper
    • Located at the base of the tank, the flapper lifts and triggers a flush of water to the toilet bowl.
  • Toilet Float
    • This device regulates the amount of water in the tank. Also called the ballcock.
  • Tank Lever
    • This connects to the handle and lifts the rubber flapper, which trips the flush.

Causes of a Running Toilet

  • The two main parts to look at are the fill valve and the flapper.
  • Remove the lid of the toilet and set it to the side.
  • If water is constantly running into the tank and the overflow tube, the toilet valve is likely the issue.
  • If water is running intermittently but not flowing to the overflow tube, the toilet flapper probably needs to be replaced.

Adjust or Replace the Toilet Fill Valve

  • Use a screwdriver to adjust the spine that runs along the side fill valve.
  • Turn it counterclockwise to lower the float cup and the water level so it stops below the overflow tube.
  • Fill valve kits include a metal clip or angle adaptor that will prevent the refill tube from going below the waterline. If the refill tube is pushed down into the overflow tube, it will cause the tube to constantly siphon water from the tank.
  • The refill tube should be attached to the angle adaptor clip and sit just above the overflow tube. (not inside the tube).

Here’s a great diagram of your toilet tank and how to determine your toilet type.

If all this sounds too technical or you decide it’s not in your best interest to try this at home, please call us! Mac Plumbing is here for any of your plumbing needs.

Be prepared with a check-up from Mac and if you do find yourself with plumbing problems, be sure to contact Mac Plumbing here or call us at (931) 552-5555.