Hold an ice cube on top of the gum until it hardens. Scrape it off with a spoon or another hard object.
Spray an oil lubricant such as WD-40 on top of any remaining gum. Wait two or three minutes and scrub it off with a rag. Clean the inside of the washer thoroughly with hot, soapy water when finished.
Remove the gum with a water-based, heavy-duty de-greasing cleaner, commonly sold in auto parts stores or in the laundry or cleaning aisle in many retail stores. Dab the cleaner on a rag and scrub off the stubborn gum inside the washer. Rinse well with wet rag.
Examine the washer carefully for any more gum. Repeat cleaning steps, if necessary. If the gum is thoroughly removed, run an empty cycle in the washer using hot water to get rid of any cleaning residues.