Originally Posted by
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BUT...........things were not sealed and he sealed them as far back as he could see.
Things were not sealed meant there was a leak. Can you explain that better. A leak not sealed is a place for gas to escape
If the smell was in the sink its self and was in the bowl area I would say it's the waste and overflow. The part that drains the sink if the water stays on and the drain plug is in the holes underneath the faucet in the bowl
Lets at least do a cheap experiment before the wall Plug up the sink and fill it half bleach and half with hot waste. Pull drain and let it go all at once. I would do this twice. If this helps knock down or stop for a while the oder than it proves that its in that drain system. I I wanted you to do it twice so if there is a little leak back in the wall the bleach will help some what of a small sewer leak of liquids.
My next alternative is to get into the wall under the sink and cut the drywall out there and look and smell to chase it. If the vanity has a full back the then some valve issues needs address. You cab call a second plummer for another opinion
See how the bleach goes. And recheck the waste and overflow on the sink
Signed 21 Boat
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