The toilet represents one of the least complicated things in your home as they work off of a basic lever system including a ballcock assembly, some valves and a float ball. It is this basic nature that makes toilet repair within your reach barring burst pipes and cracked porcelain of course.
The majority of problems you will face with your toilet can be traced back to a faulty ballcock valve assembly. There is no reason to call a plumber because replacing a ballcock assembly is easy and cheap to do and this article will show you how.
Step 1 - Draining and Prepping the Tank
Trying to fix a ballcock valve assembly while the water is running and the tank full of water is just not possible to do effectively. First, turn the water off that leads into the toilet tank. There is no need to turn water off at the street or a mainline in your basement because each toilet has its own shutoff valve. It is located close to the floor near the back of the toilet.
Turning it to the right will shut the pipe from distributing water. The tank, however, is still full of water and is covering the ballcock valve. No need to grab buckets as you can just flush the toilet. Flushing causes the lever to rise which unplugs the central line in the tank. The water drains completely out of the tank so you can work.
Step 2 - Disconnecting the Toilet Internals
As you disconnect the internal components of the toilet make sure you remember where they go. Take notes if you have to so that you can put everything back the way it is supposed to be. Check out the rubber washers inside the tank. Look for cracks or rotting. If the washers are damaged then replace them along with the ballcock assembly.
Remove the float arm by unscrewing it from the ballcock valve assembly. Unhook the tube that refills the tank from the overflow tube. An inlet pipe is at the tank bottom which can be removed by unscrewing the bolt. Grip this bolt with the wrench while gripping the ballcock assembly with another wrench. Unscrew the nut from the bottom of the tank then remove the ballcock assembly.
Step 3 - Replace the Ballcock Valve Assembly
Take the old ballcock assembly to the home improvement store so you can purchase the right one for your toilet. You can either choose a plastic assembly or a metal one. Metal can erode over time but is more durable than plastic. The choice is yours in the end. Put the new ballcock assembly in the tank.
Line it up with the hole and replace the bolt and nut. Tighten them to secure the ballcock assembly. Do your best to not tighten it too much because you can strip the threads or damage the ballcock valve assembly. Now you can replace the other components, turn the shutoff valve to the left and flush the toilet.