enter image description hereI sometimes need to clean tubes and the best way to do it is to inject some soap into them with a syringe, and for the rinsing step, rather than use the syringe to pump clean water through them it is much easier to just hold the tube up to the faucet and make a semi-"seal" using my hand.

However, I just noticed shortly after starting to do this that when I do it and only when I do it, water is visibly oozing out from the faucet assembly and also I found it leaking underneath into the cabinet.

I am fairly certain that this is not supposed to happen, meaning there is something wrong or loose with the sink installation but I'm not really sure what that is.

For example, my family used to (in a different house) use these water flosser attachments on the sink faucet, which would apply a great deal of backpressure...

Actually I'm beginning to suspect that it is the design of this faucet that the faucet itself is hollow and water can freely flow back in, so maybe the answer is to just replace the faucet with a less poorly designed one.

Or... wait. No... The problem is that when water gets anywhere up there near the faucet, it actually flows down into the cabinet now. So I think the main issue is that the seal between the faucet and the sink is nonexistent now.

Now my task is to figure out what model this is so I can learn how to disassemble it. It is some kind of Moen.

Edit: Was able to identify it as a Banbury, and furthermore that there is a set screw on the handles... however, removing the handles is not needed to loosen the faucet from the sink. The bottom gasket is indeed the issue.

3 Answers 3


Generally with a top-mount faucet like that you have to crawl in the cabinet and loosen some awkward fasteners behind the sink bowl (which may or may not include the waterline connections) to pull the faucet up so you can either replace the gasket with new, or replace the gasket with caulking or plumber's putty (without the utter hack job of just caulking it where it sits)

  • I took this as an opportunity to replace my tap with a high-necked "bar style" tap. It's made my tiny bathroom sink much easier to use, both for filling things and for ordinary washing.
    – keshlam
    May 28, 2023 at 13:19
  • Yep. I did just this. Got a new faucet to deal with the whole silly backflowing up into the spout assembly situation. I opted for a new faucet that can swivel (which is so much more practical in a bathroom sink) over trying to do something like seal the inside of the spout with silicone. Works for me.
    – Steven Lu
    Jun 4, 2023 at 2:16

I believe that you may have compromised a seal between the faucet spout upper and lower body.
The blue highlights in the attached pic is the area I am referring to.


This seam was not intended to resist water under pressure, only water that may be splashed under the spout. You may be able to better seal this seam with clear silicone, or modify your method of cleaning the tubes.

  • After I completely took everything apart everything has become clear. Indeed the original problem I was facing was that water can flow through here, the place you marked is not sealed in any way, but that's the least of its problems. the area around the spout is not sealed. so what i was doing was going to make water flow back into the cabinet anyway. I ended up getting a new faucet that does not have this silly design.
    – Steven Lu
    Jun 4, 2023 at 2:13
  • There was also a problem with the seal between the faucet main/lower body and the sink surface, which also led to water flowing down into the cabinet whenever it pooled around the faucet, which was an even bigger concern. That one could have been dealt with by just redoing that seal but the issue of water flowing back up the inside of the spout assembly so I got a new faucet and this one can be repurposed later on down the road.
    – Steven Lu
    Jun 4, 2023 at 2:15

When you are closing the water flow, the pressure builds up and the water is escaping where it can. The short answer is yes, the pipe connections to the tap, under the sink can do with a bit of tightening.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.