Five Days Servicing My Sonora Invincible
Posted: Fri Aug 01, 2025 11:09 pm
I just spent the last five days taking apart the beautiful Swiss made motor running in my 1916 Sonora Invincible. I was just amazed at the craftsmanship of that motor. Since I was unfamiliar with the motor, I took a large number of photographs which I was able to use in order to get it back together. The reason I wanted to take the motor apart was because of bumping caused by the old grease which was turning into sludge. The big challenge I faced was opening up the spring barrels. The invincible has a three-spring motor. Two of the springs reside in one oversized barrel and proved to be the biggest headache. I have to take a moment here to thank Brad Hurt who has an excellent You Tube page. His instructions for removing the recessed lids on the spring barrels was a big help. The springs were cleaned in mineral spirits and were in excellent condition. I carefully cleaned the barrels; they too were very nice. I used Mobil 1 synthetic grease mixed with graphite powder carefully coating the inside of the barrels and both sides of the springs.
Once all the parts were cleaned and assembled on my work bench, I cranked it up to check on my work. Suddenly, I heard a dreaded pop. One of the arbors popped out of a spring hook. I was forced to get the barrels out and determine which one was the problem. It was the second spring in the double barrel which was the easiest of the three to access. I was able to bend the inside hook tight and the problem was solved.
I spent most of today making adjustments to the speed control and spring-turn indicator. It's been intense work, but most satisfying. The motor is so smooth and quiet. I saw a Sonora clock company page and the clock motors looked very similar to my invincible. I intend to keep my Invincible until I'm too old to turn the crank handle. The contact sheet photos are all before pictures. After pictures are the same only much cleaner.
Once all the parts were cleaned and assembled on my work bench, I cranked it up to check on my work. Suddenly, I heard a dreaded pop. One of the arbors popped out of a spring hook. I was forced to get the barrels out and determine which one was the problem. It was the second spring in the double barrel which was the easiest of the three to access. I was able to bend the inside hook tight and the problem was solved.
I spent most of today making adjustments to the speed control and spring-turn indicator. It's been intense work, but most satisfying. The motor is so smooth and quiet. I saw a Sonora clock company page and the clock motors looked very similar to my invincible. I intend to keep my Invincible until I'm too old to turn the crank handle. The contact sheet photos are all before pictures. After pictures are the same only much cleaner.