Let's Rebuild a Swamp Cooler Motor (to use as a Dyno!) 

Thank you! Cheers!

I was not able to find OEM bearings for this motor, but since I had a lathe, I did not look really hard for them either! I would not have bothered with machining the end bells if OEM bearings were readily available though. Keep in mind, your motor could made by a different manufacturer, so bearings might be readily available. You really won't know until you take it apart and measure the shaft and bore diameters. Most newer cooler motors use ball bearings, and changing those is fairly easy and rarely necessary. This motor is made by A.O. Smith Corp which morphed into Century Corp. It uses what I suspect is a deliberately wacky size of a 3/4 inch O.D. with a metric 16 millimeter I.D. (.6299 inch) The bearings I used are 20 mm O.D. x 16mm I.D. 20mm is .787 inch, so I had to bore end bells from .750 inch to .787 inch. www.mcmaster.com/6658K33 Could this motor be fixed without a lathe? Absolutely! The approach would be different though. I would start with a very common 3/4 inch O.D. x 5/8 inch I.D. bearing like this one www.mcmaster.com/6391K247. Then Ream it to 16mm on the I.D. after pressing the bearings into the end bells. If you assemble the motor housing with the end bells while leaving out the rotor, you can use bearing you are Not reaming as a center guide for the bearing you Are reaming ensuring you get the reamer nearly perfectly straight, even by hand and without a lathe.

@@thetransformatorium7980 thanks!