Tonight, I treated my 1999 Rainbow E2 to a LONG AWAITED (5 years maybe?) spa treatment. I went to the local Rainbow dealer today and obtained a new separator and nut, and now it runs perfectly. I took the entire case apart, put all the removable plastic pieces into the tub with hot, soapy water, and wiped the motor down. I did not take the motor apart because I did not know if I could get it back together, so I left it alone. I'm very pleased with how it turned out. Side note - When the Rainbow dealer tried to take the old worn out separator off, for some unknown reason, he grabbed the separator with a pair of pliers and broke about half of the fins - which subsequently fell down into the motor - which is the real reason for doing all this. When I saw this happening, I stepped in and took the separator off normally, and as I was doing that, I saw a whole bunch of fins go down into the motor. I got most of them out tonight, but there is still one stuck somewhere inside. It's fine for now though. Fingers crossed.
(Columbus Ohio USA) 
Comes to the Rescue!
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