Enclosed is a photo of a magneto I made for my 3 HP Fairbanks-Morse tank-cooled engine, serial no. 424100, made in 1919. I couldn't find a Bosch AB-33. This magneto is a Fairbanks-Morse Type J counter-clockwise magneto. I took a hacksaw and cut the cover over the impulse off and removed all the parts off the shaft. I used a magneto coupling from a Farmall F-12 tractor because of the offset holes in it.
I made the bracket and used springs for a Webster magneto. I brazed the back half of a bracket from the F-12 onto the J magneto. It was really tricky to get it in the right spot for the magnetic field. The trip is a 1/4-inch key stock with case- hardened tip. Later I found the body of an AB-33 that was in really bad shape, sent it to John Rex and he built it up for me. He said it was the worst magneto he ever saw and I agree with that. I had faith in John and I knew he could do it.
Howard L. Abrahamson
2145 Shilhon Road
Duluth, MN 55804