A small bottle of restorer works wonders with blocked nozzles, it will need to soak for an hour or two at least, just make sure you remove any rubber seals or it will destroy them. It only takes a tiny amount of dry paint to cause issues.
I’ve got a link in that thread too, it goes to show how essential good cleaning is so you don’t have issues. You shouldn’t need to tear things down often if your regular cleaning is up to scratch