Bathroom Sink Replacement

Hello. My little bathroom sink that is a oval 20x17 was leaking so I went out and bought one and replaced it. My first time doing it and a very easy job but I may have made a mistake. When I connected the drain from the old sink to the new sink I noticed that they had not used any plumbers putty. There is a rubber gasket in there and everything was clean. So I did not use any either and now that my sink is installed I turned on the water and the drain under the sink where it comes out of the sink is leaking. Do I need to use plumbers putty or caulking under there or is it the fact that the rubber piece is old and did not seat correctly? Will I need to pull out the sink and start over or can this be fixed without doing that? Im fine with pulling out the sink as I can just re-do the caulking. I just did not see evidence that they had used any putty under there. I have enclosed a photo where the part is. Its at the underneath part of the sink up at the top. At first I hand tightened it and then when I saw it was leaking i added a small turn with a wrench. Any chance it might seat correctly by itself? Here is a pic and thanks for any advice.

Spend $20 and go get a half decent drain assembly. Those cheap plastic drains are basically throw away items. If it was used once before, you likely won't get it to seal to another sink.

Plumbers putty is not required under the sink, just in the drain hole above.

Use some putty up top, I always pipe dope that rubber underneath. And don't be scared to tighten it, you'll break that crappy plastic before you break the sink...

If that don't fix it, take matts advice, those plastic drains are crap, get ya a good brass one.

Thanks guys. Stupid question here. I am going to have to remove the whole sink, correct?

tsfrance said:

Thanks guys. Stupid question here. I am going to have to remove the whole sink, correct?

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Nah, you can leave it in there, just unscrew that big nut on the bottom as far as you can. Then you should be able to push the whole assembly up, and unscrew the collar up top then you can pull it out and re do.

Honestly if you used that rubber up top, that's prolly why your leaking. Putty should fix you up.

spcwaters said:

Nah, you can leave it in there, just unscrew that big nut on the bottom as far as you can. Then you should be able to push the whole assembly up, and unscrew the collar up top then you can pull it out and re do.

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Sounds good, thanks. Im hoping by doing what you say I will not have to mess with that damn plunger thing!

plumbers puddy is not required if the sink has an over flow.

frodo said:

plumbers puddy is not required if the sink has an over flow.

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I always use putty...even if it has an overflow, just habit I reckon.

Putty on top (not too much or you will plug the over flow) and pipe dope on the thread like spcwaters mentioned before. -personally, I like to use Rectorseal 5 underneath-

I have seen several sinks where putty was not used underneath the upper lip of the drain, and usually the bottom of the drain is corroding.

Ok guys, I got the part out easily and Im going to try the putty route first. Being a plumbing rookie here I want to be sure I am putting the putty in the correct place. It's on the threads just about the rubber gasket, correct? (photo enclosed). Now that I inspect it closely it does look like there is some slight evidence of putty being on there before.

Put putty around the collar up top. Where my left index finger is.

Then put some pipe dope on the big rubber underneath.

spcwaters said:

Put putty around the collar up top. Where my left index finger is.

Then put some pipe dope on the big rubber underneath.

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Thank You. I got everything in and nice and tight. Im going to let it sit for a few hours before I try it. With the exception of this it really has been smooth. My fingers are crossed.

No need to play the waiting game. There is nothing that needs to dry or set up.

Throw some water on it!

Turned on the water about an hour ago and not a drop of water to be found. Thanks guy, I appreciate the help. Im feeling good!

Fill up the sink, pull the drain, and see if you have any drips. This is when I find out whether I need to snug down the nuts a tad more.

havasu said:

Fill up the sink, pull the drain, and see if you have any drips. This is when I find out whether I need to snug down the nuts a tad more.

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Thanks. That's the first thing I did. Nothing leaking. Appreciate it.

havasu said:

Fill up the sink, pull the drain, and see if you have any drips. This is when I find out whether I need to snug down the nuts a tad more.

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This!! I left it out.

That is where you find leaks on the pop up or trap. Some won't show up when your just draining the running water.