I have given up on this Selectric III. Too many issues that I could not reasonably expect to overcome. It really has served its purpose however, and I will keep it around to experiment on. After all it was donated to me for free.
The final blow came when the machine began to print the wrong characters. I found the left end of the Tilt tape had come undone from the Tilt Bellcrank. While attempting to follow the instructions on re-connecting the tape I determined that the tip of the Bellcrank that hold the spring in place had broken off. This is apparently not correctable without a new Bellcrank and the work required on the carrier to replace. At that point I made the somber decision to not proceed further in attempts to revive this typewriter. It just turned out to have too many problems in total.
The good news is that I now know much more about the workings of the interposer, the carrier mechanism, and the margin bar/pitch lever. Plus now have experience with installation of interposer return springs, key lever pawl spring combs, and tilt tapes. I think I will also take the Operational Shaft out as time permits to have the experience in case the knowledge is required on some other typewriter.
The experience has already provided valuable knowledge which helped me with the cleaning and tweaking of the other Selectric III that I posses. That machine is now successfully completed.
I believe the most valuable lesson learned was to not try any repairs until your Selectric is thoroughly cleaned. Then cleaned again. Only then can you reasonably expect to know what the Selectric needs to have fixed and what was fixed through the cleaning and lubrication.
My other older typewriters in need of refurbishing are just sitting while I have devoted my time to this Selectric. Before I get back to them though, I still have a beautiful 11” platen Selectric I that I am in the process of cleaning up. Hope to have that one to show in a post shortly.
More to come............
IBM Selectric III: Flagship model produced by IBM between c.1980 and 1986.