1) Turn off the water at the tanksupply valve or the main shutoff valve to the house. Flush the toilet so the tank is emptied. It will be necessary to hold open the ballcock to darain as much water as possible.
There will be some water in the tank which will have to be cleaned out with a sponge. A songe will also be required to mop up any water in the toilet bowl.2) If the nuts won't come out, insert a bare hacksaw blade between the bottom of the toilet and the top of the floor and saw the bolts through with the blade. The metal is soft and the job will go quickly. However, be careful not to damage the flooring material with the blade.
3) Floor-mounted bowls use hold-down bolts and wall mounted bowls use hanger or mounting bolts. With your helper, lift the toilet up off the hanger or hold-down bolts and place it on a stack of newspapers or an old blanket or a rug. stuff a rag i n the closet bend to stop sewer gases from entering the room. Remember that both the toilet bowl and tank are porcelain, a form of glass, and are fragile. The toilet can chip or crack if not handled gently. If you have any doubt about handling the unit, remove the tank first from the bowl and then the bowl itself. It makes a less bulky package with which to work.
4) Turn the bowl so you can remove the old wax ring or plumber's putty. Then install a new wax ring.
The ring is available at most home center stores; one size fits all. Use the wax ring instead of plumber's putty.
5) Position the toilet tank over the hangers or hold-down bolts (use new ones if you had to cut the old ones) and gently lower the bowl down on the bolts. This is critical: The toilet must be set absolutely straight down on the bolts and wax ring. You have to get over the center of the bowl to control it's downward angle. Have your helper guide the bowl onto the bolts. If the wax ring is not crushed straight down, it will have to be replaced with a new one. Once improperly crushed, the wax ring cannot be used again.
6) Press the bowl down on the hanger or hold-down bolts so the bowl is about level. The replace the nuts on the bolts and turn them gently but firmly, so the toilet bowl is pulled down flush with the floor.
Whether you have plastic or cast-iron drain lines, the toilet will be fastened with bolts that fit into slots in the closet flange at the top of the drain. The flange is fastened to the floor(wooden) with wood screws(Fig 7)
The square-headed bolts fit in the cuurved slots in the flange and thus are prevented from turning when you install or remove the nuts that hold down the bowl. The same wax ring is used for a toilet set on plastic pipe as for ones on cast-iron or copper pipe. The hold-down nuts are turned gently but firmly to pull the bowl flush with the floor. However, do not turn the bolts too much because you can crack the porcelain of the bowl. While you have the toilet bowl off the floor, check for water stains between the tank and the toilet that would indicate a water leak. If there are such stains, unbolt the tank and replace the gaskets between the tank and the toilet as explained above. It is much easier to do this while the toilet is inverted since the nuts that hold the tank to the toilet are under the back flange of the toilet.