If swapping in a used 940 electric fan, please know the axial shaft of the fan passes through, I guess, like with the 240 electric pusher fans, a sintered (cintered?) housing or bushing, (unless on some form of ball bearing, sealed or not) and it is lubed by a heavy oil in a packing around it, so, you wanna clean that up and lube it really well with some manner of quality synthetic lube. I used mobil 1 15W50 for electric fans.

The sintering makes small holes through the material so the so the oil passes through and keeps the turning axial shaft lubed.

Also, some or all of these electric fans use brushes. And they wear, like alternator or wiper motor brushes.

I'd keep the water pump fan. Yeah, like CB says, an all metal three row radiator as you need it. If used, get your trusted auto radiator shop to boil it out and pressure test it.
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