Usually, if a valve leaks or gets clogged and sluggish, the best solution is to replace it, because valves are inexpensive. However, it may be worth your while to repair a valve like the one shown here, because it will save you the trouble of draining the tank. You may or may not need to replace the rubber parts. Your valve may not look like this one, but the steps are pretty much the same.
REMOVE AND INSPECT. Shut off water at the stop valve and flush the toilet. Remove the hold-down screws and pull out the valve’s top.Check the rubber parts; if any are damaged, replace them or replace the valve.
CLEAN AND LUBRICATE. Use a lint-free, damp cloth to clean out any debris and mineral buildup. Apply some plumber’s grease to the parts, and reassemble the valve.
Installing a Fill Valve
Replacing a fill valve is one of the most common toilet repairs, because it takes less than an hour, costs less than $10, and can make your toilet run like new. Here we show one of the most common types of valves, called a float cup, but other types can be installed in much the same way.
Other Fill Valves
These fill valves install in much the same way as shown in the following instructions, with the “critical level” mark 1 in. below the top of the overflow tube. The white-topped vertical column valve (below left) has a float inside its body. It can be easily adjusted for height after installation. The yellow-and-black unit (right) operates much the same way as the one shown in the instructions.
1. SHUT OFF THE WATER AND REMOVE THE NUT. Shut off the water at the stop valve and flush the toilet to remove most of the water from the tank. Sponge away the rest of the water. Unscrew the supply tube.
Use a wrench or slip-joint pliers to remove the nut that holds the old fill tube in place; it is located under the tank.
2. REMOVE THE OLD VALVE. Disconnect the water inlet (a thin rubber tube) from the overflow tube; it is usually attached via a clip that you just pull off. Lift the old fill valve assembly up and out. (Yours may look different from this, and may have only one tube rather than a tube plus a water inlet, but it probably removes in the same way.)
3. CHECK THE OVERFLOW HEIGHT. Use a small level to see that the top of the overflow tube is about 1 in. below the handle’s hole.
4. ADJUST THE HEIGHT OF THE FLOAT. Set the new fill valve in the hole, but do not attach it yet. Use a level to check that the critical level mark (usually “CL”) on the float is 1 in. below the top of the overflow tube. This will ensure that water rises to 1⁄2 in. below the top of the overflow tube.
If the float needs to be adjusted, twist the valve’s shank to move it up or down.
5. MOUNT THE VALVE. Once the cup height is secure, slip a rubber washer, positioned as shown, onto the valve’s threads.
Slip the valve into the hole in the tank and tighten the mounting nut under the tank.
6. HOOK UP THE WATER SUPPLY. Clip the water inlet so it will shoot into the overflow tube.
Attach the supply tube under the tank: Hand-tightening may be tight enough, but you can give it another quarter turn with pliers to be sure. Turn on the water, and test to make sure the water rises to the right level and that the unit flushes smoothly.
Dual-Flush Valve
A dual-flush toilet saves water by offering two flush levels: a small flush of about 1 gal. for liquid only and a more forceful flush of 1.2 gal. to 1.6 gal. for solids. You can replace your existing toilet with one that has a dual-flush feature, or you can save money and effort by retrofitting your current toilet with a dual-flush valve. These valves are now widely available at hardware stores and home centers.
TIP: The unit shown here is installed at the overflow tube only. Some kits also include a replacement for your fill valve.
1. REMOVE the HANDLE AND FLAPPER. Shut off the water, flush, and sponge out the remaining water from the tank. Remove the existing handle and flapper.
2. DISASSEMBLE AND BEGIN INSTALLATION. Disassemble the new valve and slide its lower part down over the overflow tube.
It has a rubber flange that fits into the flush valve seat at the bottom of the overflow tube.
3. TIGHTEN THE VALVE. To hold the lower part of the valve in place, slip a plastic cam lock down onto it.
Then slide down a rubber washer and tighten the zip tie.
4. ATTACH THE REST OF THE VALVE. Reassemble the new valve: Place its main body on top, press down, and rotate until it clicks into place.
5. INSTALL THE NEW BUTTON. Attach the new handle (or in our case, control button) into the handle’s hole, and tighten a plastic nut (counterclockwise) to secure it. Thread the control wire around so it doesn’t interfere with the fill valve’s water inlet, and slip the control unit onto the handle, pressing until it clicks into place.
6. ADJUST FLUSH FORCES. Clip the water inlet into the top of the fill valve. Test the flushes. If you want flushes to be stronger, or to use less water, you can make the adjustments for both types of flushes by simple moving an adjustment bar up or down.
TWO BUTTONS. The new control has two buttons, one for a weak flush and one for a more powerful flush.
TIP: If the existing flush valve seat is not compatible with the dual-flush valve, you will need to replace it with one that is compatible.
Excerpted from Plumbing (The Taunton Press, 2016) by Steve Cory.
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