- 1). Cut off the water supply for the toilet where you want to replace the bolts. The water supply valve is usually mounted on the wall behind the toilet. Trace the water supply hose from the bottom of the tank to the valve. Turn the knob on the end of the supply valve clockwise to turn off the water.
- 2). Flush the toilet. Continue holding down the handle until all of the water is out of the tank. Remove the lid. Wipe up the remaining water with the towels and sponge.
- 3). Insert a flat-head screwdriver into the tank bolts in the tank. With your other hand, loosen the nuts on the underside of the tank with a wrench. Remove the bolts.
- 4). Replace the bolts with new ones. Thread a nut on the underside threads of the bolts and tighten.
- 5). Restore the water supply by turning the knob clockwise. Allow the tank to fill. Flush the toilet and ensure that it is working correctly. Tighten the bolts if necessary. Replace the tank lid.
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