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Old Toilet Fill Valve Won’t Turn Off & Can’t Get Top Off

* Removing top cap of newer 400 Series fill valve
For valves with stainless steel adjustment rod

  1. If you are attempting this procedure while the valve is already installed into the tank, then it is necessary to turn off the water supply and flush the tank.

  2. With right hand, reach under the float cup and push it up. Keep right hand under the float by grabbing the valve shaft and holding it tight. Do not let the float cup drop or the valve shaft turn.

  3. With left hand, grab the cap and at the same time place your thumb on the side of the gray lever arm (see picture) and twist both the cap and the lever arm counterclockwise 1/8th of a turn. You may need to press down on the cap while making a quick twist. The valve cap will unlock.
  4. The cap assembly includes; the black cap, gray lever arm, the plastic housing and seal.

The right hand is positioned below the float cup. Lift up the float cup, which raises the gray arm at the top cap. The left hand is gripping the cap while the thumb is pressing on the raised lever arm. Turn counter clockwise.