Our Henry vacuum cleaner is not sucking properly. There seems to be
something wrong with the motor. Are there any user-serviceable parts on a
Henry motor? For example, the brushes?

I am assuming at the moment that it is either the brushes are worn or one of
the motor coils has burnt out. If it's a coil, I am afraid that poor Henry
is destined for landfill, but brushes ought to be easy enough to replace (I
assume).

The machine still runs, but it doesn't suck properly. I have, of course,
checked all the obvious things, like the hose and so on, before asking here.