Leaking galley sink

[dmksails]

My galley sink is leaking at the point where the pipe attaches to the sink drain. When I took this apart, there was an o-ring under the flange. The entire joint was also thoroughly smeared with silicon caulk - so this leak is nothing new.

It's my understanding that the only gasket needed is the white one shown and that the nut only needs to be hand tight.

I can't get this to stop leaking, no matter how hard I crank on the nut. Any suggestions on how to fix this?

I'm tempted to try putting butyl tape under and over the pipe flange. I'm afraid that if I start replacing parts I'll end up having to redo all the galley plumbing.

[model 10]

Use white silicone. I used black once and you could see it on the inside and it looks gross.

[Stu Jackson]

Butyl tape by Maine Sail or plumbers putty.

[Bycrick]

I’m betting you have a Taiwanese boat. That looks like the same fitting that I had. Just wait until the nut corrodes. I found a plastic nut that actually came in two pieces that slid together. It worked for a while, then cracked. I never could find another one. I ultimately redid the plumbing with a plastic fitting on the sink and a plastic elbow joined with hose.