As a follow up to my earlier entry I took this unit apart again and modified the blower wheel slightly to add more clearance at the outer edges of the blades. This was done by carefully removing some of the outer edge plastic material of each blade using a grinder. Hopefully the balance is not off too badly. I still hope to find a new motor one of these days. When I was preparing to put the blower wheel back in place I drilled a small hole in the center of the wheel so as to allow me to squirt some Loctite in to secure it on to the threaded motor shaft. The hole was then sealed up with some RTV to keep dirt out. After all the prep work was done the unit was plugged back in and started up and it runs very well with no noise.
