just a note to thank malc b for his answer, which i applied last night, and it worked.
a few things to emphasise, using malc's numbering:
1) be sure to unplug the electric cable from the wall socket.
6) it's definitely a two man job, as the machine should be tilted forwards, and then held there by someone else for safety.
8) undo the clip which is at the very top of the black pipe.
11) empty and clean the cup and the ball.
15) i took malc's advice at this point, but when next running the machine, the water pressure forced the black hose off, sending water across the kitchen floor.
on my second attempt, i held the black hose as high up the white neck as possible.
i then tightened the screw until it literally made an audible squeak.
many thanks, malc, for solving a problem which hotpoint don't want us to solve by ourselves.
matthew, January 2009