How do I conquer THIS problem?

[NLAlston]

Well, it's ME again.

I have attached a picture of a situation in our upstairs bathroom. We had a pedestal sink in there, which began leaking at the connection area. Now, it's a PVC pipe - attempting to capture the threads of a galvanized mating piece. I don't know if those two, differing, properties might be the causative factor - because of the difference. I've gone to Lowe's to pick up new pieces of the PVC portions, and had hoped that it would correct the issue. I found, however, that the PVC 'nut' would NOT seat securely in the threads (I could only get it about halfway on). In addition to that, the nut created no resistance to that elbow being so easily moved in and out of its insertion. I'm nowhere even near being adept at plumbing matters, but I wonder if the nut would have to be tightened all the way down, in order for compression to be achieved. Just as a note, the 'pictured' PVC elbow is the exact same size as the one it replaced.

I hope someone might have a suggestion as to what needs to be done.

Advanced thanks,
Nathan

[drainman scott]

Did you use a slip joint washer on the pipe ... if not it would cause the pipe to be loose ( pic of one below )


Also make sure the galvanized 1 1/2 " nipple threads a cleaned good ( wire brush ) to prevent cross threading which can easily happen when mating PVC to metal .



If your still having a hard time with the PVC threading onto the galvanized nipple try using a metal nut. ( pic below )

[drainman scott]

To all the Plumbers.







Yeah I know.

[NLAlston]

Drainman,

Yes, I did incorporate a 'Slip Joint Washer'. Don't know if it matters, but mine was a semi-clear one. Thanks to your suggestion I will be making another run to Lowe's, tomorrow, to pick up a metal nut. Also, per your advice, I will tackle those threads with a wire brush. I will post back with the results.

I thank you,
Nathan

[Cable or root]

Rubber washers are better than plastic washers

[fixitright]

Purple washers are best

[All Clear Sewer]

teflon tape can also be a good friend

[Ace Sewer]

it's not uncommon for the tapered threads on a galvanized nipple to run out of taper and tighten up before a plastic nut has screwed far enough in to compress the washer. A metal nut (as suggested) isn't as long and will compres the washer sooner. Or you can put a second compression washer on the trap arm to take up the axial space.