How do I fix Fan Blower motor on my Sunpentown WA9000E?

I have an older Sunpentown WA9000E portable AC unit. Never had a porblem until recently..One day, the blower motor for the fan stopped working or works very weakly. When this happens, it spins the wrong way in reverse... The AC compressor DOES come on no problem. After taking the sides off, I found that if I give the fan blower squirrel cage a spin by hand in the correct directrion, it spins up and works fjust fine.
Please tell me what is wrong and how do I fix it? I already got a replacement unit, but I still need to fix this one and use it elsewhere.
Cost for repair is not an issue unless more than a replacemnt unit.