How to Change the Fill Valve on a Gerber Toilet

Remove the toilet tank top and set it out of the way. Locate the shut-off valve on the floor next to the toilet on the left-hand side. Turn the shut-off valve all the way to the right to shut off the supply of water to the toilet.

Flush the toilet to remove most of the water in the tank. Use a sponge to soak up the remaining water in the tank. You can wring out the sponge in the toilet bowl.

Look under the toilet tank where the water supply hose connects to the fill valve that sticks out the bottom. Use a pair of slip joint pliers to loosen the water supply hose and finish removing it from the fill valve by hand.

Loosen and remove the plastic nut under the tank around the end of the fill valve. This nut should remove by hand but if not use a pair of slip-joint pliers. Remove the fill valve from the tank after removing the small rubber hose from the overflow tube in the tank.

Cut out the center of the black rubber gasket with a utility knife. Slide the gasket, which came with the fill valve, onto the end of the new fill valve with the flat larger part at the top. Push the gasket up against the plastic flange on the fill valve tube.

Set the new fill valve into the hole in the toilet tank with the smaller part of the gasket being inserted into the hole. Fasten the plastic nut that came with the fill valve onto the end of the fill valve that sticks out the bottom of the tank. Hand tighten the nut until it is snug.

Attach one end of the small rubber hose to the nipple at the top of the fill valve and insert the other end in the overflow tube in the tank. Attach the water supply hose to the fill valve underneath the tank and turn on the water supply.