The flush valve, located in the middle of the toilet, includes the overflow tube and the hole where water enters the bowl when the toilet is flushed – the hole that's covered by the rubber tank ball or flapper. This assembly includes a large rubber washer that, over time, can become worn or stiff, causing leaks.

Also, the hole in the assembly   itself can become corroded, preventing a good seal and allowing water to drip into the bowl. If any of these conditions exist in your toilet, it's time to replace the flush valve assembly.

Turn off the water at the shutoff valve, then disconnect the ballcock and remove the toilet tank. Gently set the tank upside down and remove the old flush valve by unscrewing the spud nut with a spud wrench or a pair of slip joint pliers.

Slide the cone washer onto the tailpiece of the new flush valve. The beveled side of the cone washer should point toward the end of the tailpiece. Insert the flush valve into the tank opening so that the overflow pipe faces the ballcock.

Screw the spud nut onto the tailpiece of the flush valve, and tighten with a spud wrench or a pair of slip joint pliers. Place the soft spud washer over the tailpiece, and reinstall the toilet tank. Turn on the water and check for leaks.

Installing A Plunger-Valve Ballcock
A ballcock basically is a toilet's only mechanical part. It has a number of moving components that can wear out or break. When that happens, you'll need to replace the ballcock. It's not a difficult job...

Fixing a Leaky Floatcup Assembly
A floatcup assembly is the part of your toilet that seals the opening between the tank and the toilet bowl. When the toilet is flushed, a rubber tank ball or flapper lifts out of the way and water rushes into the bowl...

Making Minor Adjustments
Toilets get used a lot, and sometimes they simply get out of adjustment. If your toilet is gurgling and seems to be losing water unnecessarily, try some minor adjustments before replacing any parts...