How to Remove and Replace a Toilet
Take the tank cover off and remove 2-3 bolts connecting the tank to the bowl. You may need to apply penetrating oil to allow loosening of these bolts. Now, remove bolt covers from the top of the bowl and loosen the bolts holding the bowl to the floor. If the bolts will not loosen easily, apply more penetrating oil or use a hacksaw to cut the old nuts. Most new toilets come with new bolts, so don't be overly concerned about trying to save the old bolts and nuts.
Lastly, remove the old wax ring. Usually, a wide putty knife will work just fine. Work the putty knife just below the flange and begin scraping the wax off in chunks. Remove immediately, otherwise, you'll get wax on everything. Place a rag into the drain to restrict odors from coming into the house.
Clean and inspect the closet flange and surrounding flooring to make sure there's no damage. Insert new tank bolts into the closet flange making sure the heads allow for maximum amount of contact with the flange material. Remove the new wax ring from the box and install at the underside of the bowl. Because the wax ring is very sticky, don't touch it. Remove the rag from the drain.
Now, lower the new bowl onto the 2 bolts sticking through the closet flange. The bolts should align perfectly with the holes on the bowl. Add washers and tighten nuts to each bolt. Alternate tightening between bolts being careful not to over tighten.
Most newer tanks come with a flush valve and fill valve already installed, however, if yours does not, insert the flush valve through the opening in the tank and tighten a spud nut (large nut) over the end of the threaded valve. Place a spud washer on top of the spud nut.
Adjust the fill valve to allow for the right level of water in the tank and install the valve inside the tank. Tighten with a nylon lock nut below the tank, by hand at first and then with channel lock pliers.
With the tank lying on it's back, thread a rubber washer onto each tank bolt and place the bolts through the bolt holes from inside the tank. Thread a brass washer and hex nut onto the bolts from below and tighten them a quarter turn past hand tight. Again, do not over tighten!
Position the tank onto the bowl by lining up the mounting bolts and the spud washer to bowl below. Place a rubber washer, followed by a brass washer and wing nut to mounting bolts and tighten evenly. If the bolts will not tighten evenly, secure them with a slotted screwdriver from inside the tank and tighten the nuts, not the bolts. Continue tightening until tank is level and secure. Do not over tighten, thus cracking the tank!!
Hook up the water supply to the fill valve with the coupling nut provided. Turn on the water and test for leaks. FINALLY!!, attach the toilet seat to the bowl with plastic or brass bolts provided with the seat through the rim and secure with attaching nuts.
Make sure the tank is secure to the bowl and the bowl is secure to the floor and there are no leaks and your new toilet is now ready for use. Congratulations!!