How to Troubleshoot a Leaking Seal Between the Sink & Drain

Shrinking putty causes a sink basket seal to leak.

The area in generic terms is called the sink basket, and therefore the sink basket seal is the cause of leaks. The seal between the sink and the drain is usually sealed with plumber's putty on the top, and a rubber gasket seal below. In time, this putty can shrink and begin to allow water to pass through either the putty itself or by loosening the rubber seal. Troubleshoot the situation yourself.

Things You'll Need

• Sink drain stopper
• Dry rag
• Flashlight or shop trouble light

Instructions

1. Insert the sink drain stopper over the sink basket. Press it tight and firm.

2. Fill the sink up with warm water. Warm water is a must because cold water might cause condensation on the outside of the basket and give you a false leaking impression, while hot water might cause the putty to temporarily expand, stopping the leak until it cools off again.

3. Shine a flashlight or trouble light on the sink basket seal from below. Wipe away any condensation or damp spots with your rag and continue to observe the area.

4. Determine the source of a sink basket leak. Look for water squirting out, driblets running down the pipe, or slow dripping from the area as a whole. If leaking is present, try tightening the sink basket lock nut; this may compress the plumber's putty and the rubber gasket and seal the leak. If that does not work, the seals must be replaced.

References

• Goliath: Stop Leaks Under the Sink
• Reader's Digest: How to Replace a Kitchen Sink Basket Strainer