Most universal flappers, fill valves, floats are designed to be compatible with standard toilets and come with assembly instructions. It's inexpensive and will quickly fix most running toilet issues.

The toilet is running because either water is running in the toilet or water is running out. You need to replace the fill valve and/or the flapper.

How to Repair a Running Toilet 1. Adjust the Float The float arm controls the water level in your tank. If it’s set too high, water will keep running into the overflow tube. Locate the float: It ...