Furnace Blower Motor Doubles as a Dust Collector

“The York furnace in our home was new,” writes William Campbell, “when the house was built in 1997. It had a 10-year guarantee. In 2007 (just past the guarantee, natch!), the GE blower motor failed. The service man took the failed motor with him. In 2009, the second motor failed in the same manner, first a horrendous squeaking, then not turning any more. I convinced the service man to leave the failed motor so that I could do a teardown.

The motor rotor is mounted on a 0.500-inch diameter shaft supported by 0.502-inch-diameter bushings in the end caps at each end of the housing. There are cavities in each end cap holding an oil-soaked foam that allows a small amount of oil to enter the bushing as needed. There are also seals at both the inboard and outboard sides of the end caps.

The end with the fan allowed house dust to infiltrate into the bushing, creating a black colored varnish in the ID and reducing the size to 0.501/0.502 inch.

The seal at the other end other end of the shaft is clean and is 0.502-inch diameter.

The shaft at the fan end had accumulated varnish and is out of round from 0.501 to 0.505  inch. It would no longer rotate in the bushing.

The shaft at the other end is clean and measures 0.500 inch diameter.

I am including the label here just in case someone from GE might be interested in improving the seals to keep house dust (a common contaminate in houses) from making their motors stop running in 2 years and helping their customers avoid a $500 + repair bill.”