Free guides / Plumbing
How to Fix a Running Toilet
A running toilet is almost always one of three things: a worn flapper, a float set too high, or a tired fill valve. All are cheap, universal parts.
Safety first
- Turn off the water at the valve behind the toilet before removing parts.
- Toilet tank lids are heavy and crack easily; set it on a towel.
Tools
- Sponge and bucket
- Adjustable wrench
- Scissors (to trim the chain)
Parts
- Universal toilet flapper (2 in. or 3 in., check your flush valve)
- Universal fill valve, if the valve is worn
Step by step
Find the cause
Lift the lid. If water spills into the overflow tube, the float is too high. If you hear a hiss and the bowl refills on its own, the flapper is leaking.
Adjust the float
Turn the float adjustment screw or slide the float clip down so the water stops about 1 inch below the top of the overflow tube.
Replace the flapper
Shut off water, flush to empty the tank, unhook the old flapper from the ears of the overflow tube and clip in the new one.
Set the chain
Leave about 1/2 inch of slack in the chain. Too tight and it leaks, too loose and it won't flush.
Replace the fill valve if needed
Unscrew the supply line and lock nut under the tank, swap in the new valve, set its height and reconnect.
Test
Turn the water on, let it fill, and flush a few times. Add food coloring to the tank; if color shows in the bowl after 20 minutes, the flapper still leaks.
When to call a pro
Call a plumber if the tank or bowl is cracked, or water leaks at the base of the toilet onto the floor.
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