Slow drip from below bathroom sink


Old 01-18-18, 10:42 PM
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Slow drip from below bathroom sink

I am trying to see what I can do about a slow drip from below our bathroom sink. If you see the attached photo, I put a red arrow pointing to the section of the sink that has water collecting.

The yellowish material is the bottom of the sink itself; the whitish material around it is some type of what looks like hard paper mache. I have run my fingers along the tubes that go above this point, and there is no water there. Nor was there any water along the sink above the point I have indicated with that arrow.

I believe that this indicated point is where water is coming out (and slowly dripping onto the floor of the cabinet). Now what I'm thinking of doing is simply applying some caulking along the bottom of the sink, where the yellow part meets the white part.

My question to you all here: is this only a stop gap measure? Is there some other spot where the water might be coming from? If this isn't going to seal off the actual hole that the water is coming from, then obviously I would only be changing the path that the leaking water is taking.

Any suggestions here?
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Old 01-19-18, 01:42 AM
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Not sure what that material is under the sink but that is not where the water is leaking from, it's just where the water is coming from.

The leak has to be at the pipe join and making it;s way to the edge of the "paper".

Can the material be removed so the true source of the leak identified?
Old 01-19-18, 05:38 AM
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I would remove the tail piece from below the sink and flange from the top side. Then apply plumbers putty to the bottom side of the flange and re-install everything. You want to use enough plumbers putty that it squishes out around the top as you tighten it down.
Old 01-19-18, 10:01 AM
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Check to make sure the aerator on your faucet is not cross threaded. Have seen instances where a leak at the aerator will back track down the inner of the faucet and drip back were you are indicating. I don't think it is a drain issue given the location and waters propensity to travel downhill rather than uphill.
Old 01-19-18, 10:17 AM
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OK thanks for the replies so far. I just realized I have another plumbing issue that will require insurance company in on it, so I will be gone for a few days. If I don't hire my handyman I'll post back my progress (or lack thereof) soon.
Old 01-19-18, 11:40 AM
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Use single sheets of toilet paper to see if there are wet areas on the underside of the sink that would suggest where the water is flowing or migrating or originating.

Could you have a leak along the edge of the sink so water sloshed on the counter outside the sink leaks down also?

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