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Repairing toilets

Find your toilet leak

If you suspect your toilet is leaking here are some simple repair directions you may want to try.* The leak may be caused by a failing flapper, tank to bowl gasket, float ball or fill valve. There are a variety of toilets on the market which have different floats and valve sealing arrangements, but leakage usually comes from the same few causes.

Unsure if your toilet is leaking? Challenge your toilet to the Leaky Toilet Test. A positive dye test in your toilet bowl means your toilet valve is leaking, whether a flapper, or plunger style toilet, this is where your repair will need to happen. Follow step 1 below. If your dye test comes back negative and you still suspect a problem, likely your water level is too high and you need to check your overflow. Follow step 2 below.

Step One: Positive Dye Test

Inexpensive and easy to replace, the toilet flapper is the number one culprit for most leaky toilets. How do you know if yours is ready to be replaced? If your flapper has a rubber seal,simply rub the bottom of the flapper with your finger. If you get streaks of rubber, it's ready to be replaced.

Other toilets have silicone seals or are entirely made of silicone. When new, they are very flexible. As they age they harden. If your silicone flapper is not very flexible anymore, it's time to replace it.

Take your old flapper or gasket with you when purchasing a replacement so you get the right fit. Knowing your toilet's brand or model number may also help.

Float ball typ tank
Float Ball tank

To replace your flapper:

  1. Shut off water at the valve
  2. Flush the water that is in the tank and note the length of the flapper chain (E) as it is attached to the handle (this will save you time when you install the new flapper)
  3. Remove the old flapper, install the new flapper into the toilet and adjust the chain as it was before you took the old flapper off
  4. Check the valve seat (D) for corrosion and clean it if necessary. Dry the valve seat and sand it smooth with fine sand paper.
  5. Turn on the water and test again to ensure the leak has been repaired

Does your toilet keep running unless you jiggle the handle (G)?

The chain (E) that controls the flapper might need to be adjusted for the flapper to sit properly on the valve seat (D). To fix the chain, first clean it and make sure that it isn't too long or too short. If the chain is kinked, it should be replaced with a ball-type chain. If needed, tighten the nut that holds the toilet handle (G) to adjust the trip lever (F) properly. If this does not work, the handle may need to be replaced.

Have a dual flush toilet?

Try watching this video for repair tips:

Step Two: Is the water level too high?

If the water level in the tank is too high, it may continuously spill over the overflow tube (A), creating a large leak. The correct water level is about one-half to one inch below the top of the overflow tube.

To lower your water level:

  1. Turn the float rod (J) adjusting screw (H) clockwise to lower the water level one or two centimeters below the overflow tube (you may also gently bend metal float arms if you have a float ball or adjust the float cup along the metal adjusting rod).
  2. Replace the screw if it is corroded or stripped
  3. Flush after making adjustments to test whether the water stops at the proper level
  4. Ensure the refill tube (I) is securely inside the overflow tube (A) no deeper than five cm (if the water level is too low, you may not get an effective flush)

What if the water level stays the same?

If this doesn't lower your water level, the float (B) may be waterlogged and needs replacing or the float assembly may need replacing. Some have a float ball, other a float cup and the method for adjusting the water level varies.

Remember to bring your old plumbing part to the store with you to ensure you get a matching acceptable replacement part. After replacing parts in your toilet, always repeat the toilet leak test with food colouring to ensure you have a good fit.

*This information is provided for your benefit. If you do not feel comfortable making these adjustments please hire a plumber. The City of Calgary will not be responsible for any damage because of faulty repairs.