I had the same problem my machine however was not plumbed into the wall, i have to bring it out every time I use it, not a big deal.
With it being an older machine, was difficult to get parts... THEN!!! A very nice service man from Cascade Appliances, Speers Road, Oakville, Ontario, suggested that my husband take apart the pump - which my husband did, and it had a lot of rust in it, even though everything in the pump was plastic and VOILA!!! it works like a charm, hope this solution helps anyone else with a similar dilema (ps my husband is a bit of a handyman so get someone like that to fiddle with it) Good luck
WizzenWitch, October 2008