Hi everyone, new here and first home buyer with a bit of a fixer upper.
This is not my first time fixing a tap, but this one has me scratching my head. I have a cold water unit presumably from 2008 (pictured) that provides water to my washing machine. It's leaking from a busted o ring washer on the gasket, but when I go to remove the spindle washer to take out the gasket the whole tap body spins. I can't seem to get the spindle nut to budge, and I'm starting to think it might be either an integrated unit or just so old and gummed up that it won't disconnect.
Things I've tried:
-standard pliers on spindle nut
- a pipe wrench on spindle nut
-WD40 on the washer (visible) and inside the fitting around the gasket
- standard pliers and a hammer to try and loosen.
None of the above has worked in removing the spindle nut. I was going to go get a needle nosed shifter or a really big socket wrench to do the job, but unsure if that would even fix this. Anyone have any advice on what this fitting is, if the spindle can be removed, or if maybe I should just call a plumber and get this thing removed/replaced/handled?

