How to Repair Toilet Tank Problems

©2006 Publications International, Ltd.Toilet tank troubles are both common and annoying, and they could be costing you money in wasted water. Most problems, however, can be eliminated easily. This is a cross section of a typical toilet tank and its components.

Compared with a clogged toilet, tank troubles can seem relatively insignificant. Yet strange noises or continuous water running can be more than annoying; it can cost you money in wasted water. Fortunately, you can eliminate most tank troubles quickly and easily.

Once you know how the toilet works, you can start to look for the source of your toilet tank problems. First, lift the lid off your toilet tank. When you trip the handle on the tank to flush the toilet, a trip lever is raised inside the tank. This lever lifts wires, which, in turn, raise the tank ball or rubber flap at the bottom of the tank. When the flush valve opening is clear, the water in the tank rushes out past the raised tank ball and into the toilet bowl below. This raises the level of water in the bowl above the level of water in the toilet trap.While the water is rushing out of the tank, the float ball, which floats on top of the water in the tank, drops down. This pulls down on the float arm, raising the valve plunger in the ballcock assembly and allowing fresh water to flow into the tank. Since water seeks its own level, the water from the tank pushes the bowl water out into the drain, causing a siphoning action that cleans everything out of the bowl. When all the water is gone from the toilet bowl and air is drawn into the trap, the siphoning stops. Meanwhile, the tank ball falls back into place, closing the flush valve opening.


As the water level rises in the tank, the float ball rises until the float arm is high enough to lower the valve plunger in the ballcock assembly and shut off the incoming water. If the water fails to shut off, there is an overflow tube that carries excess water down into the bowl to prevent the tank from overflowing. Once you know how a toilet properly works, you are ready to solve common problems like water constantly running or strange noises coming from the tank. Find out specific steps to solve these problems in the next section.

Solving Running Water in Toilet Tank

©2006 Publications International, Ltd. If your toilet runs continuously, check the guide and the lift wire  that raises and lowers the tank ball to be sure they are aligned properly.

If you hear strange noises or water constantly running from your toilet tank, it is an annoyance that can be fixed. Use the following steps if water flows continuously out of the tank to the toilet bowl and down the drain:

Step 1: Lift up on float arm. If water stops, you know the problem is the float ball doesn't rise far enough to lower valve plunger in ballcock assembly. One reason could be float ball is rubbing against


side of tank. If this is the case, bend float arm slightly to move ball away from tank side.

Step 2: If ball doesn't touch tank, continue to hold float arm and remove ball from end of arm by turning it counterclockwise. Then shake ball to see if there's water inside it, as weight of water inside could be preventing ball from rising normally. If there is water in ball, shake it out and put ball back on float arm. If ball is damaged or corroded, replace it with new one. If there is no water in ball, put ball back on, and gently bend float rod down to lower the level float ball must reach to shut off flow of fresh water into tank.

Step 3: If the above steps don't solve the problem, check tank ball at flush valve seat. Chemical residue from water can prevent this ball from seating properly, or ball itself may have decayed. Water will seep through flush valve opening into toilet bowl below. Turn off water at toilet shutoff valve, and flush toilet to empty tank. You can now examine tank ball for signs of wear and install new ball if necessary. If problem is chemical residue on lip of flush valve opening, take some wet-dry emery cloth, steel wool, or even a knife and clean away debris.

Step 4: If excess water still flows through toilet, guide or lift wire that raises and lowers tank ball may be out of line or bent. Make sure guide is in place so wire is directly above flush valve opening. Rotate guide until tank ball falls straight down into opening. If lift wire is bent, try to bend it back to correct position, or install new one. Make sure trip lever rod is not rubbing against anything and lift wire is not installed in wrong hole of rod; either situation could cause tank ball to fall at an angle and not block opening as it should. 

Step 5: If neither float ball nor tank ball is at fault, then problem must be in ballcock assembly. For complete instructions on how to fix a ballcock assembly, click here.

The tips and guidelines in this article will help you avoid having to put up with annoying noises from your toilet tank.

©Publications International, Ltd.