New Cooling Fan Motor

I recently bought a new radiator fan motor for my 1992 Buick Century. It has some slots in the front and back, large enough to make the rotating coils visible. My old, squeaky fan motor (still in the car) seems to be completely enclosed. Before I install the new fan, will the slots be an issue? Will the inside of the motor collect a lot of dirt which will shorten its life? Did anybody have any problems with motors with openings?

All the brands of motors illustrated in Rock Auto seem to have openings, at least in the shaft end of the motor. Bear in mind that alternators always have big slots on their sides exposing their windings and it doesn’t cause a problem. The same would apply to a motor as applies to an alternator although a radiator fan motor is in a more vulnerable spot.