Mark,
Put about 8 tablespoons of Cascade or or any other dish washing detergent in a large stainless steel pot( the best) or your sink and fill with just enough cold water to cover the parts to clean. Soak for at least 8 hours or overnight.It will clean spinach, parsley and other stains. Acme Juicer recommended it 35 years ago. I'do it and it works.If you want a good centrifical juicer get a Acme 6001 or the similar Omega with a stanless steel top, bowl and strainer. You can use paper filters to line the strainer not clog it and is easier to clean.