That look like one of the original selectric I/Os which means that mechanically it is very much like the standard Office Products (OP) selectric. The sound that it is making when running suggests that the motor belt is cracked or is missing teeth. Unlike the OP selectric the IO used a more powerful capacitor start motor that was capable of ripping the teeth of the belt if the mechanism was jammed. It looks like the dust covers are missing there should be covers over the cycle shaft and op shaft. When you types it looks like the carriage did not move and also you noted that carriage return does not work, This may be due to the "cords" being broken or off the drums. There should be two white nylon cords, one attached to each side of the carrier, the one on the left goes around behind the frame an wraps onto a drum there, the drum for the one on the right should be visible when you look inside. The visible drum has a bevel gear on the face that meshes with two bevel gears on the op shaft. That look like they have springs around them. There should be a nylon shoe that presses against the on one the left when you press the carriage return key. I found this online which may be of some help to you, https://archive.org/download/bitsavers_ibmtypewrishootingTheIBMSelectricTyp… This manual will at least help with the mechanical part of the IO. The cover latches are on either side and will be half buried in the likely now rotten foam on the sides. They have a slot in the top you can stick the blade of a screwdriver into and move the top of the latch towards the front. The original IO used 48V solenoids to operate the mechanism as a printer. There will be 6 for selection, one for shift, one for cycle clutch, and one for each function, likely tab, carriage return and line feed. The basic operation is the selection magnets are picked to pull the desired latches and then the cycle clutch magnet is pulsed to take a print cycle. To maximize the print speed, the selection magnets get picked as the cycle clutch passes the rest position that way the cycle clutch never latches up to give you maximum print speed. This is timed by contacts operated by cams at the left end of the cycle shaft. There will also be a block of contacts under the selection assembly that are used to detect what key is pressed and in some versions of the 2970s ( there are lots) there was a set of contacts designed to verify that the correct character was printed. The ones I worked on most where teller terminals used in banks and they had these check contacts. There is also shift feedback contact and a contact that is call the long function contact that is activated during tabs and carriage return. Other things I found that may be helpful: https://www.evernote.com/shard/s17/sh/0b92c5b8-2366-4101-aa9d-4c999325ae6a/… Training videos, These appear to be the original slide and audio tape training for the OP selectric. https://www.youtube.com/playlist?list=PLHT97Xg067fCkONv0EKmS74a-csWbttXl I don't recall there being any specific manuals for for the IO, but I was working on these daily and did not need to refer to manuals often. Paul. On 2015-11-23 4:50 AM, Mike Ross wrote: