Replaced my faucet and it wont stop leaking

[Amateurplumber1]

deleted

 

[CountryBumkin]

Sounds like threads stripped (see locknut). I think you are stuck - this is probably a good time to replace the drain assembly with a new one. Or you may be able to get a new rubber sealing washer from one of the big box stores (thicker may get you back into the area where the threads are not stripped - if there is such an area).
Usually some plumbers putty goes under the metal lip on bottom of strainer on inside of the sink nothing is needed on the bottom - if everything on top is correct.

 

[Sponsor]

 

[Cacher_Chick]

Throw the plastic drain away and buy a decent plated brass one.

I use a light coating of putty on the gasket and putty on the threads for the locknut. This is not as much to seal anything as it is to lubricate and help ensure everything goes together nicely during assembly.

 

[Dj2]

Take the drain set apart, and re-do it. I wouldn't use silicone, but putty.

I suspect you didn't tighten the nut enough.

Regarding metal drain sets and plastic drain sets: both have advantages and disadvantages. I've been using plastic parts forever and see no reason to stop using them.

 

[Reach4]

So whenever I tighten the damn nut, it'll slip and then loosen.

As others have pointed out, it sounds like your drain parts are inferior.

 

[DonL]

All you need to to do, Is use KY and hand tighten.

How do you strip the thread ?

It helps if the outlet is not clogged.

 

[Terry]

I looked to see the larger rubber washer under the bowl.
Is there one there?