"Speedy Jim" wrote in message
...
Leaking at the putty should *not* cause a drip below.
That will only allow water in the basin to go down the
drain.

The secret is to seal the rubber Mack gasket to the
threads of the pop-up drain and also to the basin.
I use silicone sealant. Apply to top surface of the
Mack gasket and also liberally to the threads.
If you don't seal the threads, water will spiral
down them.

Jim

But Jim, where would the water spiraling down those threads come from?
Seems to me it can only come from the basin, 'cuz that's where the
water is, and if you follow the threads upward
you come right to that joint between the metal of the drain meets the
porcelain of the
basin, i.e., where the putty is. Conversley, if that joint is sealed
by the putty
AND THE DRAIN PLUG IS DOWN there is no way water can get to those
threads.
That's the test I'm talking about. I dry everything, close the plug,
and fill the sink up about 3-4".
After a bit the threads beneath the nut are wet. Not much, but wet
nonetheless.

Now, I agree that if the drain plug is up (or the basin is full and
flowing into the
overflow hole) the rubber Mack gasket (didn't know that's what it's
called) can
be involved.

I'm no plumber, but that's what I see when I look at the drain
plumbing.

Ed