How to fix a kitchen sink drain leak
The flange in a kitchen sink is designed to create a watertight seal between the sink and the plumbing beneath it. The seal gets exposed to dramatic fluctuations in water temperature, and over time it will eventually break down. When it fails, a leak will develop under the sink, and if not repaired, water damage can occur to the wood beneath it. Fortunately, repairing a leaky kitchen sink flange can be accomplished in one afternoon.
- Shut off your garbage disposal at the main circuit breaker if your kitchen is equipped with one. This will prevent any accidental operation of the garbage disposal during the repair.
- Clear out anything that is stored under the sink to give yourself ample room to work. Use a flashlight or portable lamp to illuminate the plumbing underneath the sink.
- Loosen the drainpipe that connects to the sink using the pipe wrench. If the drainpipe will not break free, spray the connection with penetrating oil to loosen it.
- Remove the nuts that are connected to the underside of the flange. If you have an older flange that uses nuts and bolts, remove the nuts and push the bolts upward to remove them.
- Lift out the flange carefully from the top of the sink. If the flange will not break free, use a flat-head screwdriver to gently pry it upward.
- Remove the old rubber gasket from the flange and use a wire brush to completely clean the flange. Use the wire brush to clean around the drain of the sink, making certain to remove any lingering pieces of the old gasket.
- Apply plumber’s putty to the drain of the sink where it meets the flange. Place a new gasket onto the flange and drop the flange back into place.
- Tighten the nuts on the bottom of the flange and reconnect the drainpipe with the pipe wrench. Use a rag to remove any excess plumber’s putty that has squeezed out of the connection.
- Open the faucet and inspect the plumbing for any leaks.
Things You Will Need
- Pipe wrench
- Plumber’s putty
- Penetrating oil
- Flat-head screwdriver
- Wire brush