Moen shower arm leaking

[mossymeadow]

After finishing our new shower earlier this month, we've been fighting issues with our Moen shower arm leaking behind our wall. Probably should have put the drop ear a little bit further out towards the shower, but it's done now. We're getting grout cracking underneath the shower arm and I don't even want to think about what the wall looks like inside. If you pack toilet paper around the arm it gets soaking wet in under 60 seconds. Hopefully our wall system will help prevent too much mold in the cavity (durarock, redgard, tile).

I've tried putting new tape on and threading it...over and over again. More tape, less tape, etc. Doesn't help

After reading different threads on here, I took a look at the threads on the shower arm. They are more square, rather than having sharp Vs like the dog ear elbow does.





I suspect this is the cause of the constant leaking, but I am not sure of the solution.

Options:
a) get a new shower arm that has better threads. If this would help, what brands should I look for?
b) use more teflon tape
c) clean out the inside of the dog ear elbow to make sure there's no junk or corrosion in there (WD-40 and a toothbrush? Steel wool?)

I'm so frustrated with this Moen shower valve and associated parts! The illustrations for installing the valve were wrong so now our shower handle sticks out an extra 1 1/4 inch, and now this . . .

 

[Terry]

I would get a different shower arm. I don't like the look of those threads. Shower arms are generic. They all have 1/2" threads.

 

[Sponsor]

 

[hj]

Unless you get an elbow with threads that have a "flat bottom", (which you will not), the threads are not going to match up and seal.

 

[Plumber69]

Maybe its cracked or a bad solder joint. Id also try plugging it off and pressurizing it

 

[mossymeadow]

My husband watched the kids tonight while I ran out (by myself! what a treat!) and got a new shower arm from Home Depot. All they had was Glacier Bay, but the threads looked good. Some heavy duty pipe tape and soft set pipe sealant and it looks like it's not leaking anymore. Thank you so much for the guidance!