Toilet bolts rust easily because of the condensation that forms when cold water runs through the toilet. This condensation makes a perfect enviroment for rust to form on the toilet bolts. Often, when toilet bolts are rusted they cannot be loosend with a wrench. The only way to remove the rusted toilet bolts when this happens is to cut the bolt off. This article explains a simple procedure of removing toilet bolts when you have rusted toilet bolts that won't back off with a wrench.
step 1 Turn The Water Off
Turn the water off at the valve supplying the toilet. This is a safety precaution, you will soon be removing the toilet and need to shut it off anyway.
step 2 Cut The Rusted Toilet Bolts Off
Since the toilet bolts cannot be removed using a wrench you will need to cut them off using a hacksaw. When removing toilet bolts it is very important to not cut the porcelin when cutting the rusted bolts. Always cut between the nut and washer, never cut under the washer next to the porcelin. This can cut and crack the porcelin.
Before using a hacksaw blade to cut, look at the blade and notice the direction it cuts in. There is usually an arrow or wording on the side showing the direction that the blade cuts in. Hold the blade so that it cuts as you push it away from yourself. Create a "handle" for the blade by wrapping the rag around the end of the blade that is closest to you.
Position the blade between the nut and washer, if there is one and push the blade back and forth to cut the bolt. It takes a little patience and elbow grease but the brass bolt will eventually be cut.
After the bolt is cut thru you will be able to slide the washer offf and then lift the toilet. See Removing A Toilet section to finish preparing the toilet for removal.
using a dremel tool The Dremel Tool or other similar tool also works well. These tools are very high speed and can quickly cut the porcelin on the toilet so be careful. Cut in the same location described above, between the bolt and metal washer.