Why are blower motors "factory sealed"?

Dear Car Talk | Jan 01, 1993
Dear Tom and Ray:
Joe
RAY: It's standard practice for all manufacturers to "factory seal" their blower motors. What that means is that the metal covering on the blower motor is folded over and welded, so you can't open it up and replace individual parts of the motor. It's a lot less expensive to make that way.
TOM: So if you're looking to recover $86, I think you have a better shot in the Publishers Clearinghouse giveaway than you do with Oldsmobile, Joe.
Joe
RAY: It's standard practice for all manufacturers to "factory seal" their blower motors. What that means is that the metal covering on the blower motor is folded over and welded, so you can't open it up and replace individual parts of the motor. It's a lot less expensive to make that way.
TOM: So if you're looking to recover $86, I think you have a better shot in the Publishers Clearinghouse giveaway than you do with Oldsmobile, Joe.
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