Preventing a sink strainer from leaking?

Question

I've had issues with my kitchen sink's strainers and I've replaced them both, but I'm still having some problems with one of them. I did what I think is fairly normal procedure: undo the piping + basket nut, pop out the basket, clean everything well, wrap plumber's putty underneath the basket, press down, reassemble nut and piping under the sink and then peel away the excess putty on top. It (seems) to have worked fine for one side, but not the other; it still has a slow drip, almost like condensation, when the sink is filled with water.

I've pulled it apart and replaced the putty and gasket a couple of times now, but still can't seem to get this one to work. I've run hot water down the tap and managed to move the nut a tiny bit more, although if I tighten it much more then I'm worried that the nut will crack or I'll squeeze the gasket out. There's no play in the sink strainer itself. When I was tightening it down it did twist maybe 15 degrees as I was tightening it, but afterward I kept water in it for around 30 minutes with no issues. That was about a month ago, and the water just started to start to drip.

I haven't seen any more putty leak out of the sink since, and there's no play in the sink strainer if I try to wiggle it a bit. One thing I did notice with this side is that it seemed like the hole might have been a hair bigger than the otherside; I had more plumber's putty on the bottom with this one. Although I would have thought that with a good plumber's putty seal and really tight gasket that I should be fine.

Any suggestions? This doesn't seem like rocket science but I'm starting to get a little frustrated.

Answer 1

Channellocks are great for replacing sink strainer drains. I've never had a sink drain where I needed something like a basin wrench because they are generally easily accessible.

As for the leak:

1)Make sure you don't have a faulty basket strainer. Make sure there are no cracks or other defects in it. You said it looks like condensation underneth so I'm guess that means water is actually on the outside of the plumbing and it's not just leaking past the strainer plug and into the drain.

2) Is it leaking from the sink drain or from one of the drain connections below? Be sure to check the drain connections closely to make sure it's not leaking from them. If you've used putty on top and a rubber gasket and paper gasket on the bottom (make sure the rubber gasket goes directly against the sink and the paper gasket between that and the nut), the likelyhood of it leaking is very slim. You can overtighten the nut (and other plumbing parts that have gaskets) and actually cause leaking issues so be sure not to go crazy on it. Tightness is realitive but it should be tight enough that once you're done you can't twist it by hand and it doesn't move when you tighten the drain pipe back on.

3) Be sure to check for any chips and/or cracks that water might be able to seep into and leak out. If there are chips and/or cracks, you can try repairing them with some special epoxy or using silicone instead of putty. Silicone will be much more of a pain to remove later but it does come off with some persuasion. If using expoxy, be sure to let it fully cure before putting the strainer back on.