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Over dinner several months ago, a friend of Lisa and I mentioned that she had a motor from an exhaust fan that quit working. I knew about this fan in the kitchen of her parent’s house because it was original to the house and very cool. After discussing the problem I told Kathy that these old motors were made to be repaired and I was willing to check it over. Since it came from a ranch style house I knew that it was at least 60 years old. When I opened the bag I discovered that this Pryne & Co. Model 13-1050 motor and fan blade was preserved with 60 years of cooking grease. The data plate said the bearings needed to be lubricant periodically, but I’m sure bacon grease is not what the engineers had in mind. 🤔 Armed with gloves and a putty knife, I removed the worst of the layers of grease then soaked it with Simple Green. Several hours later I scrub the motor clean with a parts brush and wiped off the remaining gunk. Then it was time to see what lurked inside.

I expected more solidified bacon grease but found very little crud. I discovered what I expected. The bearings were dry but the surfaces were not damaged. How the bearings and shafts survived without oil and no damage is amazing.

After cleaning the internal parts and clearing the lubrication holes, oil was applied to the bearings and reassembled. Unfortunately the motor was still dead. At this point I figured it died due to lack of lubrication on the bearings causing the stator to over heat and short out. Now the project turned into finding a replacement, which I did, and removing the various parts that would be needed for the new motor. But one bushing for the fan blade refused to budge.

After soaking overnight with a penetrating oil called Kroil, and applying a little gentle prying, the last piece was removed this afternoon. As I was putting all the parts in a bag, I decided on a whim to try the motor one more time. And it worked! My first thought was that there must have been just enough drag in the bearings that it stalled the motor? But that did not make sense. Not being satisfied with not knowing, I pulled the motor apart to clean up the bearing that I could not access due to the fan bushing. After putting everything back together it was dead again. After more fiddling, the problem appeared to be where the wires connect to the plug blades.

After 60 years of grease, steam, and neglect, I suspected the copper wire corroded and failed. After more cleaning and soldering the wires to the plug there was still a intermittent connection. After more disassembly there was a broken connection from the stator to the power lead.

At this point I decided to replace the wires from the stator to the plug. Once these connections were all soldered and the motor reassembled everything worked without further issues. It is satisfying to be able to fix a problem instead of throwing away a perfectly good motor. It is now back where it has been before I was born.