Step 5 · Connect and Adjust the Chain
Connect the clip on the new flapper's chain to one of the holes on the flush lever arm (the rod connected to the outside handle). The chain's length is critical. Adjust it so there is just a small amount of slack, about 1/2 inch, when the flapper is closed. If the chain is too tight, it will prevent the flapper from seating properly, causing a leak. If it's too loose, the flapper won't lift high enough for a full flush, or the excess chain could get caught under the flapper. Once the length is correct, you can use scissors or wire cutters to trim any significant excess chain.