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Homeowner Guide · 5 min read

Toilet Running, Leaking, or Slow to Flush

Toilets are one of the simplest fixtures in your home and one of the most over-quoted. The vast majority of issues come down to three parts inside the tank: the flapper, the fill valve, and the flush handle assembly. All three are easy to replace.

A toilet that runs constantly

Take the lid off the tank and watch. If water is trickling from the tank into the bowl through the drain at the bottom, the flapper is not sealing. Replace it. If water is overflowing into the central tube (the overflow tube), the fill valve is set too high or has failed. Adjust the float, or replace the fill valve.

Both parts are available at any hardware store and install in 15 to 30 minutes.

A toilet that leaks at the base

Water around the base of the toilet usually means the wax ring underneath has failed, or the bolts holding the toilet to the floor have loosened. A wax ring replacement is a real but not difficult repair. It requires removing and reseating the toilet, and most plumbers charge a flat rate for the job.

If water only appears at the base when the toilet is flushed and not otherwise, the wax ring is the likely culprit. If water is present continuously, check the supply line and tank-to-bowl bolts first.

A toilet that flushes slowly or weakly

First, check the water level in the tank. It should be about an inch below the top of the overflow tube. Low water means a weak flush. Adjust the fill valve to raise the level.

If the tank level is correct, the issue is usually clogged rim jets (the small holes under the rim of the bowl) or a partial drain clog. A bent wire and a flashlight will clear the jets. A standard plunger or a closet auger handles most clogs without a service call.

Key takeaways

  • Most running-toilet fixes are a flapper or fill valve replacement.
  • Continuous leaking at the base usually means the wax ring.
  • Weak flushes are often low tank water or clogged rim jets.
  • A closet auger handles most clogs that a plunger cannot.

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