Try Phil Wood products; Phil's Tenacious Oil, originally developed for bicycle lubrication, is a fine lubricant which stays put. They also make Bio Lube, a lighter lubricant, and Waterproof Grease. Not affiliated with Phil Wood, just a satisfied customer.
Thanks for the advice, Steve. It's always difficult to find the appropriate oil for appliances. I've restored several turntables, and the advice there for motors is the same -- don't use engine oil. The difficulty is that everyone has a jar of motor oil handy, whereas getting ahold of those various mineral oils which adhere properly and don't leak out of small motors and bearings (as the quickly do, leaving things dry again and liable to seize up) is hard.
I've got a portable dehumidifier for coping with life in the redwoods, where mold grows on everything outdoors, including plastic (that's not a joke), and the amount of moisture indoors in winter, spring and sometimes summer is pretty amazing. We got an industrial-grade one with a longer warranty, but the reason it's lasted this long (about 8 years) is by voiding the warranty. It's a quality machine and worth the money we spent, but nowhere in the original specs or warranty were there any instructions on maintenance: only a "don't open it up or you void it" statement. But the amount of household dust the fan pulls in shut the motor down after the first 2-3 years. So once every couple of years we spend an hour or two taking it apart and cleaning or oiling the insides as needed.
So a simple dose of oil saved both the humidifier and the washer? Sounds like a viable do-it-yourself fix-it kit that might get some traction if sold on the Internet, maybe in some of those appliance chat rooms where users come to share their woes!
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