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Water Not Filling Up Toilet Tank After Adjusting Float

* Raise or Lower Height of Fill Valve:

If the lock ring below float cup is whitish in color, no height adjustment can be made.

The four critical areas of a toilet tank are:

Before any adjustments are made determine how high or low you want the valve to be adjusted. Each revolution of the body of the valve equals ½" of height adjustment. Once you know the required height you want to reach in inches, proceed to Step #1.

  1. Remove the cap assembly.

    1. Turn off water supply and flush the tank.

    2. Reach under the float cup with right hand and push it up. Keep the float cup lifted up with your right hand under the float by grabbing the gray or black shaft and holding it tight. Do not let the float cup drop or valve shaft turn.

    3. With your left hand, grab the top cap while placing your left hand thumb on the side of the lever arm, then twist both the cap and the lever arm counter clockwise 1/8th of a turn. You may need to press down on the cap while making a quick twist. This will unlock the top cap assembly allowing you to lift it off the valve body.

    4. The cap assembly includes: the cap, lever arm, and plastic housing with seal. The seal is the rubber disc that has a pin coming thru it.

  2. Remove the refill hose from the nipple of the fill valve.

  3. Now turn the upper body of the valve in the counter clockwise direction to raise higher. Turn the upper body one click at a time (clockwise to lower; counter clockwise to raise higher.) You will hear and feel a "click". You may even think you broke it. This means it is moving. One 360 degree revolution equals ½" higher (or lower). If you want the water level to be 1" higher, for example, then go around twice in the counter clockwise direction. If there is resistance, don't be afraid to turn harder. It will not break. Usually after the first "click" it gets easier. Do not move the lock ring.

  4. Reconnect refill hose to nipple. Reassemble cap assembly to valve body.

    Place cap assembly on top of the valve body with the lever arm over tab next to refill tube. Press down on cap while turning lever clockwise 1/8th turn.

    Turn on water and check water level.

    Make a finer adjustment of the water level by using the water level adjustment clip or a plastic screw adjustment rod located on the front of the black float cup.