[mr0077]

Teflon might be a temporary fix if it is leaking between the nut and the bowls, since that would seal the threads between the nut and the bowls, but if it is leaking between the nut and the flared inlet pipe it likely won't work, as that flare fitting relies on the nut holding the two flared fittings together for a seal. I'm not sure how you would fix the leak at the flare. You need to tighten the nut to the bowl (gently, don't overtighten), and then HOLD that nut with a wrench while you tighten the flare nut. If not, the inlet pipe will twist when you tighten it against the snug nut, then when you let go of the flare nut, the inlet nut will back off and leak...