How to Stop a Running Toilet

Fix a toilet that won

⚡Quick Answer

Usually the flapper (rubber seal at bottom). Replace it: turn off water, flush, unhook old, attach new. Check chain has slight slack.

Remove tank lid. The flapper (rubber seal at bottom) is the most common cause. If warped or worn, water leaks into bowl.

💡Add food coloring to tank. If color appears in bowl without flushing, flapper is leaking.

Turn off water (valve behind toilet). Flush to empty tank. Unhook old flapper from overflow tube. Hook new flapper on, attach chain.

💡Take old flapper to hardware store to match size. Universal flappers work on most toilets.

If water keeps running over overflow tube, lower the float. Turn adjustment screw or slide float arm down.

💡Water level should be about 1 inch below overflow tube top.

Chain should have slight slack. Too tight = flapper can't seal. Too loose = can get caught under flapper.

💡About 1/2 inch of slack is ideal.

Up to 200 gallons per day! That's $50+ per month on water bills. Fix it ASAP.

Every 4-5 years, or when you notice running/leaking. Chlorine in water degrades rubber faster.

Slow leak through flapper. Tank slowly drains, then fill valve kicks on. Replace flapper.

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