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Plumbing in the Home/New bathroom sink stinks/tub drain issue



I installed a new sink (like this one: on our bathroom 6 to 8 months ago.  When removing the old one, the trap metal and horizontal drain leading to the wall connection crumbled so I replaced it with PVC.  Due to the location of the trap and the way the drain comes out of the wall I had to use a flexible trap (like this one:

About 2 months ago we noticed a smell coming from the sink, most notably the overflow holes so I had a plumber replace the drain and trap thinking the smell was caused by the baffles in the trap holding water.

That doesn't appear to be the case.  The smell is back.  It smells musty, almost like mold but I can be sure.  The drain empties quickly and seems to hold water in the trap.  It's not a smell like there's no water in the trap, it's just musty.

Any thoughts on what it could be?

I also have an issue with my tub.  House built 1950.  Original tub and drain.  I'm told the drain is brass.  Every once in a while the drain is very slow.  A plumber told me to use a plunger on it and that only works some times.  I've snaked it but the last time I couldn't get the snake to go toward the trap, it kept coming out of the overflow.

We've been using a drain cleaner and that seems to fix the issue and the problem stays away much longer than plunging or snaking.  I've attempted to replace the pipes but they are all behind finished ceiling and walls.

What else can I do to fix this issue besides replacing the pipes?  We use a hair trap in the tub to prevent most of the hair from draining.


Tub waste and overflow, correct direction for snaking.
Tub waste and overflow  
Hi James,
Technically, those "flex traps" are illegal and do not meet code. As you mentioned, they tend to trap debris and scum and are more prone to clogging.

Next, I'm not a big fan of chemical drain cleaners, especially with plastic piping. They can generate a substantial amount of heat when sitting in one place working on a clog and that can damage the pipes. Many are very aggressive and will damage even metal pipes.

As for snaking out the tub, you're doing it in properly and that's why you're having a problem.
Plungers only work on a closed system. A tub drain is not a closed system since there is an overflow. All you do with a plunger is move water up and down the overflow pipe which generally has little effect. The correct way to snake a tub drain and be able to get through the trap is NOT for the actual tub drain but by removing the overflow cover and the linkage and staking straight down through that. A typical quarter-inch snake cannot make the sharp 90 turn at the connecting point of the tub drain and the overflow. I'll attach a picture so you can see what I mean. Down through the overflow is the correct snaking procedure.

As for the problem with the musty smell, it just might be a build up of organic material and scum inside the overflow drain channel of the sink. This is a difficult place to access easily. This overflow channel which is cast into the sink actually connects into the pop up drain assembly. I have had some success by removing the actual pop-up plug and shoving a wadded up rag down the drain outlet to plug up this opening from the overflow drain. Then, using something like a turkey baster, I filled overflow drain channel with common household bleach and let it sit for a few hours. After a few hours have elapsed, pull out the rag and flush out the drain channel with hot water. This should help.

Good Luck,

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Dana Bostick


Pretty much any residential plumbing questions. For "item specific" details such as a specific model of fixture, I will need to research and there may not be any useful information available. Note: I live and work in Southern California. We do not, as a rule, use hot water or steam heating systems, oil fired boilers or private water wells so my knowledge in those areas is pretty limited. There are others here on AllExerts that can probably answer those questions better.


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