Toilet Won’t Stop Running? This Part Inside the Tank Could Be the Reason
A toilet that keeps running can sound like water leaking into the bowl long after a flush. Sometimes the tank fills, stops for a moment, then starts again. Other times, water never seems to shut off.
When Brittney’s husband opened the tank to make the repair, one part became the focus: the fill valve. It controls water entering the toilet, and a worn or faulty valve can cause problems with filling, water flow, and noise.
Replacing it meant working inside the tank and below it, but not removing the toilet. Once he shut off the water and drained the tank, he could disconnect the old fill valve and pull it out through the opening in the bottom of the tank.
Start by draining the tank
Shut off the toilet’s water supply, then flush. With the supply closed, the tank drains without filling again.
Some water will remain at the bottom, so place a bucket beneath the tank before disconnecting anything. That bucket becomes important once the valve comes out.
Disconnect the water line below the tank
Follow the water supply line to the connection under the toilet tank. Unscrew the hose from the tank, keeping the bucket underneath to catch water from the line and tank.
A mounting nut holds the fill valve against the bottom of the tank. Remove the nut, washer, and O-ring before trying to pull the valve out. A crescent wrench can help if the connection won’t turn by hand.
Now the entire old valve comes out
Once the mounting hardware is off, the fill valve lifts out from inside the tank. Water trapped around the valve can drain through the opening as it comes free, another reason to leave the bucket below.
Removing the valve leaves an open hole through the bottom of the tank. That single opening is where the replacement valve will sit.
Replacement valve needs to match the tank’s water level
Before securing the new fill valve, attach its refill tube. Valve designs differ, so the exact connection can change by model. On the valve used here, the tube pushes onto the valve opening to form a tight connection.
Height matters too. The valve isn’t meant to be dropped into the hole and tightened at whatever position it happens to reach.
Set the new valve inside the tank and compare its position with the toilet’s water-fill line. On this model, the valve extends or retracts until the corner of its top cover meets that line. Once the height is set, the valve locks in position.
The valve can then be secured with its mounting nut beneath the tank. The original installation calls for tightening that nut by hand rather than cranking it down with a wrench, which can damage the valve.
Refill tube has one specific destination
A clip attaches to the top of the flush valve and holds the refill tube where the water needs to go.
If the tube is too long, trim it rather than forcing it into a sharp bend. It should form a smooth curve from the fill valve to the clip without a kink that restricts water flow.
Final flush tells you whether the repair worked
Reconnect the supply line under the tank and turn the water back on. Let the tank fill, then flush several times.
Don’t check only whether the running sound stopped. Watch the supply connection under the tank for leaks, check water coming from the new valve’s refill tube, and make sure the tank stops filling at the correct water level.
If those three points check out, the fill valve replacement is complete. What sounded like a problem buried somewhere inside the toilet can come down to one removable part sitting in plain sight once the tank lid comes off.