Inspect the water supply line, shut-off valve and connectors to the tank. Shut-off valves should be exercised twice a year. Cheap brass shut-off valves will corrode over time and should be replaced if corrosion is present. It is best to use braided stainless steel supply lines. Do not substitute the cheaper braided plastic ones and especially if there is a young dog in the home who can easily chew through the line.
Remove the lid from the tank and inspect the components, also check the water level to insure the tank is not over-filled. Check the bolts which attach the tank to the base, these bolts are made of metal and may rust and deteriorate over time. Now, move to the outside of the tank where it attaches to the base of the toilet and insure there is no moisture present.
The toilet attaches to the floor with a flange and bolts and then seals to the drain with a wax ring. Inspect the area around the base of the toilet looking for any discoloration in the floor coverings or signs of moisture. The base of the toilet should not be fully caulked. If water does leak from the drain you want to ensure that water can move out from under the toilet.
Recent research has shown that many common toilet cleaning products can damage components of the toilet, thereby causing significant leakage; some manufacturers may even void the warranty. If you choose to use these cleaners, the toilet must be flushed at least once per day. As an alternative, use the in-bowl toilet cleaner rather than the in-tank cleaners.
Many toilet repairs can be handled by the homeowner. Instructions for do-it-yourself toilet repair can be found through simple searches on the web. However, the majority of new toilets range from only $100-$200 and it may simply be easier to have it replaced.
For more on this or other home care subjects, contact Scott at www.scottsauer.com.