Toilet Repair: A How to Guide on Repairing a Toilet

Because it gets used so often, your toilet has a good chance of eventually needing repair. Although some people find the prospect of repairing a toilet distasteful, as long as you flush it once or twice before beginning, you will be dealing with clean water only. (If it won't flush, see Unclogging Toilets)

How a Toilet Works:

The inner parts of a toilet are fairly simple. When someone flips the flush handle, a chain reaction of events starts. The handle lifts the trip lever, which in turn pulls a chain that lifts the tank flapper off the flush valve. (In older units, a lift rod raises a tank ball.) As water rushes down through the opening into the bowl, the reservoir of water and the waste in the bowl yield to gravity and pass through the toilet's trap, down through the closet bend, and out a drain line.

Inside the tank, the float (or in older systems the float ball) descends along with the outrushing water until, at a predetermined level, the shutoff rod it attaches to trips the ballcock, which is a water supply valve. At the same time, the tank flapper settles back into the flush valve, stopping water from leaving the tank. The ballcock opens to shoot a new supply of water into the tank through a refill tube and into the bowl through the overflow tube. When the float rises to its filled position, the ballcock shuts the water off.

A wax ring seals the toilet bowl to a flange on the closet bend and keeps water from leaking out onto the floor. A spud gasket seals the tank to the bowl.  

Common Repair 1: Tank Continuously Trickles

Problem: Water continuously trickles or runs into tank and/or bowl.

Causes and Cures:

1. Water level is too high. To fix: Adjust trip lever chain, adjust water level in tank, or replace leaky float.
2. Flapper or tank ball isn't sealing properly. To fix: Clean the flush valve under the flapper, or replace worn flapper.
3. Ballcock is faulty. To fix: Repair or replace ballcock
   

Common Repair 2: Bowl overflows

Problem: Bowl overflows when flushed. Toilet flushes incompletely.

Causes and Cures:

1. Trap, drain or bowl is partially or completely clogged. To fix: Run a toilet auger through the toilet (see Unclogging Toilets,Related Projects), or clear drain (see Clearing Main Drains and Sewer Lines, Related Projects).
   

Common Repair 3: Tank leaks

Problem: Tank or bowl leaks. Leak appears as a wet spot on the floor.

Causes and Cures:

1. Water is spraying against the lid. To fix: Anchor the refill tube so it sprays into the overflow tube.
2. Gasket between tank and bowl is faulty. To fix: Replace the spud gasket.
3. Tank is cracked. To fix: Replace the tank.
4. Wax ring is not sealing. To fix: Pull up the toilet and replace the wax ring (see Replacing Toilets, Related Projects).
5. Bowl is cracked. To fix: Replace the bowl.
   

Common Repair 4: Tank "sweats"

Problem: Drops of water appear on the outside of the tank.

Causes and Cures:

1. Condensation occurs due to difference in temperature between the air and tank water. To fix: Buy an insulation kit and install in the inside of the tank.