I have a rather old (1975) Lennox 011 series hot air furnace that had the burner replaced around 1985. I believe it is a Beckett burner, btu have not found any info to verify that. Recently it started making a strange noise when starting. I removed the pump because I could turn the motor, but the coupler did not turn. It has some kind of centrifugal clutch fastened to the fan hub. The burner runs fine, I have 100 psi discharge pressure. I have been unable to find any parts listing to get a number of the "clutch". Anyone on here with a similar experience?