Disassemble a tap – help me Obi Wan Kenobi…

Seeking advice on how to shift a seized tap part.

Our bathroom taps are cartridge type and wall mounted. The cartridges are knackered and need replaced. I can strip the hot tap down to the final part, which is threaded onto the pipe work behind a false wall.

Except it’s seized on. It’s getting regularly doused in a penetrating oil but refuses to budge. The metal collar that sits around it slips off, exposing the joint. I’m spraying penetrating stuff into the cylinder and around the join. Hot tap has a slow drip.

Being perfectly cylindrical there’s almost no purchase on it. That said, I got the cold off using this method (plus copious bad language). Plumber didn’t want to know, saying best thing was to cut the pipe behind and start again.

Ideas welcomed. Heat? Cold? Some sort of Unobtainium spanner?

I’ve got one of these – rubber strap wrench – and it’d be the first thing I’d reach for.

https://www.axminstertools.com/boa-constrictor-strap-wrench-610000?utm_source=tag&utm_medium=affiliates&utm_content=2266&tagrid=65198679&glCountry=GB

I can only offer encouragement, because although I am a plumbing liability I recently removed and descaled some cartridges in my house, measuring them up and acquiring some replacements as I did so instead of paying the plumbers I asked to look at them several hundred to replace the mixer because their suppliers didn’t have matching cartridges.

Use the rubber coated arms of your adjustable pipe wrench pliers to grip the smooth surface. If you own any?

Rubber strap wrench is your best bet – same you use when servicing a dropper post.

Rubber strap wrench is your best bet – same you use when servicing a dropper post.

yes, in fact that’s why I’ve got one, and just about to do an air can service too. So pretty handy. Various versions widely and cheaply  available at toolstation/screwfix etc.

Sometimes, if the thread is a bit seized, giving it a tighten up tweak first can break the seizing, and then let you unscrew it.*

*And sometimes, it’s now just even tighter….

Does that collar at the back come off, any grub screws visible from underneath?

Are you using a proper big pipe wrench to try and get it off?  One of those set so the slippy bit is right up in the jaws is usually good enough for most things.  Rubber strap wrench will cause less damage though

IME the Unior suspension strap wrench is far nicer than the generic plastic and rubber variants.

Thank you all. Rubber strap device will be on order and I can, once more, look like a hero.

Until I order the wrong flipping cartridge that is…

A couple of wraps of inner tube offcut can be used with a wrench of some sort. Wrap the tube so it’s tightening down when trying to loosen the nut.