I took off the old shower arm and showerhead and bought a new 1/2 inch shower arm and new showerhead but the new shower arm will not screw into the wall pipe, the new arm its too big, I threw away the old so can't put it back on or compare or see if there was an adapter.Maybe there was an adapter on it an is that what I need to get for this new arm to screw into the wall pipe? What size adapter? Im a single widow woman an have to do this myself an cant afford a plumber, i know it has to be an easy fix and I'm tired of trying to screw this shower arm for the 100th time an not getting anywhere!can anyone help me?



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My very first thought is that you aren't getting the pipe in straight. Every shower arm that I have ever seen is 1/2" iron pipe size threading and has a corresponding female thread inside the wall. If the pipe in the wall isn't secured properly, it may have twisted slightly when the old arm was removed, and now you are trying to screw in the arm at an angle to the female threading. One trick you can use is to push the arm into the receiving threads and rotate it slowly counterclockwise until you feel it drop or feel a little 'tick' of a shake as the threads drop into alignment, then begin rotating clockwise. If it doesn't grab within 720 degrees of rotation, there is something else at play.

I have tryed all of that, as I put the new arm to the old pipe inside the wall they match in size, this pipe inside of the wall and old shower head an arm I threw away were from 1943,and I believe were not a standard size?? I have been trying for two weeks now to get the arm pipe in, I'm thinking of taking out the wall area behind where the shower is in the other room and take that part off the pipe in the wall and see what's really going on, and if I still can't get it screwed in with both parts in my hand, I'm just going to take the new arm an old pipe part to my local hardware store an let them help me. You didn't say anything about an possible missing adapter I may have thrown away if it was still attached to the old arm, I feel like there had to of been something like that maybe and that's why I can't get this new arm into the old pipe, because I'm pretty sure their the same size in diameter. Any other suggestions before I tear out opposite wall???



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Sounds like the threads from the first old arm are still in the drop ear, get a flashlight and confirm, then youll need an easy out to remove

That's a possibility, but the op said she removed the old one so I assume it unscrewed. Installing a new drop ear and getting it properly anchored from the back side of the wall is a pain most of the time. If the old one was from '43 it is likely iron pipe from the shower valve to the drop ear and will require a reciprocating saw to cut out the old bracing behind it and if it was nailed into place, then a saw or the careful application of a nail bar to pry the brace from the drop ear. Either way, you run the risk of causing enough vibration that a questionable joint inside the wall could give way at the same time. If the 90 for the shower arm is visible or if it is copper, then you have a much easier job. Since you still can't get the shower arm in, opening the wall behind is really the next step to take. It is possible that someone used a different sized pipe and threading but unlikely. If they did, you would be better served to open the wall up and change it over to a standard sized fitting anyhow. Once you get in there, let us know what you find and we can guide you better at that point. Or, you might be ahead in time, money, and repairs to get a plumber out there that deals with this on a regular basis. They may be able to get done what you have not; if they can't, they should have all the tools to get the job done (except for the wall repair afterward)

post a picture.

is it possible your old shower arm you unscrewed has another piece left in there?

I hate when that happens........ Replacing the/a shower arm does take a bit of talent to accomplish. To begin, you don't toss old parts until you are finished with the job. Most shower arms are the mostly the same. Professionals know that not all shower are the same.

It begins with knowing the brand and model of what you have and if you don't, taking pictures, rather than trying to describe, may be your best approach. If you place your finger into the opening ... you should feel threads... all the way back to the end.

Please don't begin to tear down the wall as it could get a lot more expensive to repair and replace a new wall that doesn't..... leak. It might be wise to have a neighbor ... have a look, at your shower supply to verify the issue as two or three heads are better than none.

Can you provide pictures of your shower supply and controls?
Best Wishes

One possibility, but not likely for a shower are that old is that the thread broke off the old one and is still in the pipe in the wall. I said "not likely for one that old", because it is more common with modern arms. There was NO "special" size arm EVER, so yours is supposed to fit. If you start cutting walls, and it will probably be a superfluous task, then you will spend a lot more than a plumber would cost.



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Galvanized systems did NOT use "drop ears". It was an elbow with the riser strapped to a board.

I agree with KC. I'd bet money that the female fitting inside the wall shifted ever so slightly when the old shower arm was removed, making it difficult to align the new arm dead center, square straight and true. Forget about diffrent pipe sizes, adaptors and broken threads still stuck inside. I'd bet that the pipe/fitting was clamped to a stud indside the wall after the original shower arm was installed, and before the back wall covered it up, which put a "strain" on the inside pipe, and now it doesn't line up with the hole for the shower arm. This would be especially true if the hole for the arm was small and did not have much clearance. You need a good flashlight and a way to look directly into the wall to see the orientation of the female fitting. Stick a screwdriver in and see it you can make the fitting move side to side or up and down. If the hole is really tight, remember the new arm should have a trim bezel much larger than the hole, so you might be able to carefully use a small chizel or flatblade to "nibble" out the hole a little bit to allow you work from the shower side of the wall instead of tearing out the back side wall for access.

Find a way to safely get up there, so you can see straight into the opening. Use a flashlight, and you can see if something doesn't look right. Use an old toothbrush (not hubbies) to clean the threads. Sometimes you have to slow down to speed up.