Heard a chirping noise coming from my combustion fan motor and I pulled off the outside cage that protects the fan on the outside of the motor. When I did, the fan disk came flying off. The stinking set screw came loose. I've turned off the thermostat to get the furnace shut down and as soon as the fire is out, I will kill the power and put the fan back on. Which way does the flange that has the set screw in it face? Does it face the motor or does it face outward? Obviously will make a difference with air flow.