How to Fix a Toilet Overflow Pipe

Replace the overflow pipe in your tank with a new one.

A constantly running toilet could be the result of a broken overflow pipe. These pipes are part of the flush valve assembly and serve to siphon off excess water in the tank in case the fill valve fails. The bottom of the pipe empties into the bowl below, which can drain off any excess water. Because these parts are relatively inexpensive, the best way to fix a toilet overflow tube is by replacing it entirely.

Things You'll Need

• Adjustable wrench
• Pliers
• Overflow tube assembly
• Silicone grease

Instructions

1. Turn off the water supply for the toilet with the broken overflow pipe. Look underneath the tank to find where the water supply hose connects to the tank. Trace this back to the wall or floor where it meets the water supply valve. Turn the knob on the end of the valve to the right and cut the tank's water supply.

2. Lift up the lid of the tank and set it aside. Press down on the flush handle. Continue holding down the handle to keep the flapper open and allow all the water in the tank out into the bowl.

3. Wipe out the inside of the tank with a sponge or towel. Set an old towel or blanket on the floor.

4. Unscrew the coupling connecting the supply hose to the underside of the tank. Use the pliers, if needed. Unscrew the nuts from the underside of the tank with an adjustable wrench.

5. Unhook the flapper chain from the top of the flapper on the inside of the tank. Unclip the water overflow hose from the top of the overflow tube.

6. Lift the tank off the back of the bowl and set it on the blanket or towel.

7. Look on the bottom of the tank for the retaining nut holding the bottom of the overflow tube in place. These are generally about 3 or 4 inches in width. Unscrew this counterclockwise.

8. Reach inside the tank and grasp the overflow tube firmly by the base. Pull straight up to lift it up and out of the tank.

9. Apply silicone grease to the underside of the rubber part of the new overflow tube base. Insert this into the bottom of the tank. Align so that the flapper opens towards the front of the tank. Secure from beneath with the retaining screw.

10. Reconnect the chain to the top of the flapper. Clip the overflow hose into the top of the overflow tube.

11. Lift the tank up and set it on the back of the toilet. Insert the tank screws, with the threads pointing down, into the tank so they poke out through the bottom. Secure the tank by tightening the tank nuts over the screws.

12. Screw the coupling for the water supply hose back into the underside of the toilet tank. Turn the water supply handle to the left to turn the water back on and fill up the tank.

13. Flush the toilet and make sure that it is working correctly. Adjust the water level in the tank, if needed. Replace the lid.

References

• Ask the Builder; Toilet Repair Instructions for 10 Common Problems; Tim Carter
• Toiletology 101: How to Fix a Toilet Flush Valve; Kay Keating
• Mr. Fix It: Toiletology 101