I have an elderly Hotpoint Aquarius WMA33 washing machine. It works fine during "wash" cycles and water pumps out okay but on "rinse and spin" water gushes out of the soap powder dispenser. It happens after the rinsing phase; just as the spin phase begins. When I tried it with the soap dispenser removed, I could see the water was coming back up from the drum - and there's quite a lot of it. At the same time there is a small amount of water coming out of the rear drain-pipe, so the pump appears to be working. Any ideas?