On Thu, 24 Aug 2017 20:29:33 -0400, Bob Engelhardt
wrote:

I have a single handle shower control like the ubiquitous Delta (swings
up & down and side to side). It is leaking and I have the replacement
cartridge, but I cannot get the handle off. The cartridge has a 1/4"
square plastic shaft that sits in a socket in the handle. Held by a set
screw that I have removed (1 only). I'm assuming that the handle is pot
metal and in 18 years of use some corrosion has occurred and bound up
the shaft.

I have put Liquid Wrench in the set screw hole and let it sit, for days.
I have put some heat on the handle, but it's chromed and I was
cautious in the heat's use.

Sometimes, you can put the screw in and leave it 1 turn from
tightened, then tap on the screw with a small hammer while pulling on
the handle. With nylon/plastic, that's all kinds of iffy, but...

Sometimes, a whack with the plastic end of a medium screwdriver will
break things loose enough to yank off.

Got a pic? That would help me remember where the other screw is
hiding, if there is one.

So, is the original shaft metal and the replacement nylon? If the
original is metal, chances are that the setscrew forced up a mound
around its tip as it bit into the shaft. That may be what you're
fighting. Have you tried putting some wood protectors around the back
and pried out on the handle? The metal in the handle is usually
softer than that of the shaft, so it may score as it comes off, but
that may not hurt anything. A small riffler file should take care of
it if necessary. Pry on both the setscrew side and its opposite. Does
it rock? Keep working.

Last, but not least, most replacement cartridges come with
instructions and exploded diagrams. gd&r (Sorry, had to do it.)

-
I am a Transfinancial--A rich person born in a poor person's body.
Please stop the hate by sending me money to resolve my money
identity disorder. --anon