Replace a faulty fill valve assembly

If the fill valve leaks, won't shut off completely, or keeps running after float adjustment, the entire valve assembly needs replacing. Universal fill valve kits fit most toilets and take about 20 minutes to install.

Steps

1. Shut off the water: Turn the supply valve behind the toilet clockwise until fully closed. Flush the toilet and hold the lever down to drain as much water as possible.
2. Remove remaining water: Soak up leftover tank water with a sponge into a bucket.
3. Disconnect the supply line: Place a towel under the tank. Use an adjustable wrench to unscrew the supply line coupling nut from the bottom of the tank.
4. Remove the old valve: Unscrew the locknut holding the fill valve from outside the tank and lift the old valve out.
5. Install the new valve: Set the new fill valve to the correct height per the kit instructions, insert it into the tank hole, and hand-tighten the locknut. Reconnect the supply line.
6. Test: Turn the water back on slowly and check for leaks at all connections. Adjust the float so water stops 1/2 to 1 inch below the overflow tube.

Tips

• Fluidmaster 400A and Korky QuietFILL are widely recommended universal fill valves
• Hand-tighten the locknut first, then give it a quarter turn with a wrench to avoid cracking the tank
• Replace the supply line hose if it is rigid, corroded, or older than 10 years