Trying to Replace Shower Arm

I'm trying to replace the shower head and armThe arm is okay.It seems to me that there was
with a new one without having to do too much.Iduct tape around the arm; I guess it was to keep
live in an apartment.I was trying to unscrew thethe flange from falling off which I don't see
arm and it doesn't budge. The flange that goeshappening and also there aren't any leaks in the
into the wall isn't spackled on tightly.arm itself. Oh well, I cleaned it, with vinegar too;
So, it was easy to lift the flange and see that theIt's fine. I notice a tiny bit of corrosion but since
arm going into the wall is covered with whiteoverall it's just dandy, I'm not going to mess with
spackle or something.I'm not sure what to doit.
about this. Should I remove the spackle orAny recommondations for how to make it stick
whatever it is and then unscrew the showerfully to the wall again? I notice some excess
arm?water-based "tub-caulk" at the edge of the flange
It may be a water-based 'tub caulk' that set upI may want to remove to make it look better.
and got brittle. They used that on the backside ofBut it seems to me that the reason there is
the flange to keep the flange from falling awaysome caulk at the edge is because there is some
from the wall.open space there that the flange itself can't hide.
Some of the more expensive flanges are thickerThis shower is old and so I assume the reason
and have a set screw in them. The cheaper onesthere's so much of the caulk is to prevent
are just friction fit, but often do not stay put. Ifleakage of any kind. It makes sense; until
that is the caulk I am thinking of, it has a reactionsomething needs to be replaced LOL.
with moisture and turns into concrete. It is soHowever, the new showerhead seems to have
tough to remove that if it is on a porcelain tub, itmuch better water pressure which is great
can actually take off the porcelain when you trybecause I had to alert the landlord that the
to scrape it off! Take a guess how I know.diverter wasn't working; the knob and flange
Try stabbing it with a sharp instrument or pointycame off (this is a three-knob shower; div being
nail and see if it is at all spongy. If not, you havethe center knob)... the result was water came
some jackhammering to do, before you will bethrough the tub faucet and through the shower
able to unscrew that arm.as well when the knob was twisted one way; and
The strange thing is it's not just around thewhen it was twisted the other way, completely
flange; it's around the arm and the wall itself. Theout of the faucet.
stuff around the flange was pretty goopy when IThe plumber I think did something with the
by hand removed the flange.diverter and sealed it all and the knobs work
I just checked again. It's a little mushy but prettyokay. But the problem was the water was still
firm; it looks like it's wrapped. The problem is itleaking a little bit from the faucet when it should
seems to go way into the wall. Well far enoughbe coming completely through the showerhead.
that I can't see where the end goes!The showerhead had much less water pressure.
Maybe I should just forget about replacing theIn the future I may reapply the flange though as
arm. I was doing it for cosmetic reasons.I loosened it to see what was behind it.The new
I've decided to leave it alone. Yep; I don't want toshowerhead's pressure seems to be really an
have to ask the landlord to come up afterimprovement and the water coming out of the
damaging something. A great guy and I don'tfaucet is minimal. so I'm pleased with the way
want to put something else on his shoulders!things turned out.
Thank you for your response though.