- 1). Turn off the water to the tank. Locate the water shut-off valve, which is usually located on the wall behind the toilet. Rotate the knob clockwise to turn off the water. Flush the toilet and allow the water inside the tank to run out.
- 2). Remove the tank from the toilet. Unscrew the plastic coupling that connects the water hose to the inlet valve on the inside of the tank. Unscrew the tank bolts with an adjustable wrench. Hold the bolts in place with a screwdriver on the inside of the tank as you twist off the bolts. Lift the tank up and off the toilet bowl.
- 3). Examine the tank closely. Look for any cracks. Check the cone gasket at the bottom of the tank. If it is cracked or torn, it needs to be replaced. A torn cone gasket can cause your American Standard tank to leak water whenever you flush it.
- 4). Insert a tube of silicone caulk into your caulk gun. Trim off the end to the 1/4-inch mark. Repair any cracks by applying a thin bead of silicone caulk along the crack. Press the caulk into the crack with the tip of your finger. Allow it to dry.
- 5). Replace the cone gasket by pulling off the old one and slipping a new one into the outlet on the bottom of the tank.
- 6). Replace the tank on the back of the bowl. Replace the tank bolts and washers with new ones.
- 7). Wrap the tank inlet with plumber's tape. Attach the plastic coupling to the tank inlet and tighten it hand tight. Turn on the water supply and allow the tank to fill. Flush the toilet and check for proper operation.
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