This sounds like a lot of your previous questions but none of the scenarios match up.
I have a shower in the basement of my 1928 house. I bad smell is coming from the drain. It looks like the drain doesn't match up with the 3-4" cast iron floor pipe and they used concrete to direct the water over a couple inches. I do not know if it has a Ptrap, I assume it doesn't from the smell. The previous owners and the people before that did not have any problems with the smell. Looks like it is vented, don't have any problems with flow of water from shower or toilet. I can feel cool air on the back of my hand coming from the drain. I have run the shower periodically to make sure it wasn't an evaporation thing. No luck though.

I did plug the drain to make sure the smell wasn't coming from somewhere else. When I did that the smell started coming from the hole in the shower knob (I took the cover off the knob). I assume this is because the drain is not sealed tight with the bottom of the shower. Seems like it gets worse in the winter.

Thanks for any help.
Pete

Good morning Pete,
First let's address the smell. Most bad oders in bathroom drains come from rotting hair mixed with grease from the soap. Try this. Tonight before you go to bed pour 1/2 gallon of bleach down the drain and let it set overnight. Next morning flush it down with a few large pans of boiling water. The bleach will start to dissolve and soften the hair and make it slippery and the boiling water will melt the grease and flush the mess out into the main. Now see if that smelly drain doesn't smell sweeter? You MUST ascertain that there is indeed a "P" trap on the drain. Sewer gas is hazardous to your health and the methane in it is explosive so making sure it's trapped and not open should be your first priority. Let me know what you find and if the smell was helped. Regards, Tom

Well, that seems to do the trick. It has been 1 week and no smell. (the bleach smell finally went away too)

Thanks for the advise, it was in the nick of time as I was ready to tear the stinky thing out!

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