How do seal the bottom of the sink/plastic overflow outlet on an enameled steel lava

[stouto]

Had an experienced plumber (30 years experience) install a new replacement Briggs Homer 3002 lavatory in my bathroom on November 11, 2011. A new supply line, P-Trap, and pop-up drain stopper was also installed at the same time. I have had plumbers come out three times to fix a small leak at the bottom of the sink/plastic overflow drain opening without success. The pop-up assembly has been replaced and reinstalled with new putty several times. This has been a sink from hell and is giving me nightmares. Photos of the leak and plastic overflow are attached.

The Briggs CS rep asked if silicone sealant was used on the drain pipe that goes into the plastic overflow opening on the bottom of the sink, and if the plumbers had installed sinks with plastic overflows on the bottom of the sink. I know that no silicone was used since I watched them try to fix the leak. Pipe dope was used on the threads of the drain pipe. Don't know if they have installed plastic overflow type sinks in the past . I have used these plumbers several time in the past and they are competent. Sink installation and other plumbing work is what they do every day.

Could you please tell me how the bottom of the sink/plastic overflow outlet on an enameled steel lavatory should be sealed?

 

[havasu]

I myself would give it another quarter turn and check for a day or two. If that doesn't stop the leak, give another quarter turn.

 

[Caduceus]

I agree with havasu. I have NEVER needed silicone sealant for a lav drain installation nor has it ever been recommended from a manufacturer as part of the installation. The leak looks like it is coming from between the friction ring and the gasket. That would usually indicate that the nut is not tight enough. Maybe a little pipe thread sealant on the surface of the gasket between the friction ring and the gasket would allow more tightening of the nut without damaging the gasket.

 

[phishfood]

I ALWAYS use pipe dope on the threads. I want to see pipe dope in the thread below the nut. The company I work for uses some of the lower end faucets, as we do mainly apartments, so maybe some of the higher end stuff doesn't give so many problems. But I can say without hesitation that applying pipe dope to the threads cuts down on leaks such as this drastically, at least with the faucets that I see everyday.

And as far as I am concerned, any manufacturer of plumbing fixtures that is afraid of pipe dope or the like touching their fixtures needs to find a better material to make their fixtures out of.

 

[johnjh2o]

Loosen the nut on the pop up and place plumbers putty between the gasket and the cheep plastic overflow and re-tighten. If you over tighten the pop up the plastic overflow will collapse.

John