Fix Running Toilet
Learn how to fix a running toilet by inspecting and repairing common issues with the flapper, fill valve, and float.
Tools
- Adjustable wrench
- Screwdriver
- Towel or sponge
Materials
- Replacement flapper (if needed)
- Replacement fill valve (if needed)
Safety
- Turn off the water supply to the toilet before starting repairs.
- Wear gloves to protect your hands from dirty water and cleaning chemicals.
- Dry up any spilled water promptly to prevent slips.
- Do not overtighten plastic parts to avoid cracking.
- If you notice leaks after repair, stop and consult a professional.
Steps
Step 1: Turn off the water supply
- Locate the shut-off valve behind the toilet and turn it clockwise to stop water flow.
Check: Ensure water is completely off by flushing the toilet and confirming the tank does not refill.
Step 2: Remove the tank lid
- Carefully lift the toilet tank lid and set it aside on a flat surface.
Check: Check that the lid is placed securely to prevent breakage.
Step 3: Inspect the flapper
- Look at the rubber flapper at the bottom of the tank. If it is warped, cracked, or doesn’t seal properly, it may need replacement.
Check: Confirm the flapper is sealing tightly against the flush valve.
Step 4: Replace the flapper if necessary
- Disconnect the chain and unhook the old flapper from the pegs.
- Attach the new flapper and reconnect the chain, ensuring proper length (slightly slack when at rest).
Check: Test the flapper movement by pressing the flush lever and ensuring it drops back into place.
Step 5: Check the float and fill valve
- Examine the float to ensure it moves freely and is not set too high.
- Adjust the float arm or screw to set the water level about 1 inch below the top of the overflow tube.
- If the fill valve is faulty or leaking, replace it according to manufacturer instructions.
Check: Verify the float does not stick and the fill valve shuts off water at the correct level.
Step 6: Turn the water supply back on and test
- Slowly turn the shut-off valve counterclockwise to restore water.
- Allow the tank to fill and flush the toilet several times to check for proper operation.
Check: Ensure the toilet stops running after each flush and there are no leaks around the base or inside the tank.





