A few days ago a colleage gave me his 20 years old card reader for my HP 41. As I started trying it, there was an dull sound, like the e-motor got stuck, the inserted card was not pulled through the reader anymore.
After I get some informations about repairing the card reader, I disassembled it, removed the rubber from the rubber-gear-wheel compenent (because the rubber got a jelly like feeling, an the tiny white roll was sticked on the rubber roll), I cleaned the whole mechanisim in put two small o-rings on the shaft, assembled everything and was very happy, that it worked fine, but only for a few moments. After a short time there was the same dull noise, like the motor or the gear was blocked.
So here are me questions:
1. Are there any recommendations for the o-ring size?
2. are there any alternatives for using o-rings?
3. Is it necessary to grease the whole mechanisim, and if yes, with what kind of lubricant?
4. Do you guys had similar problems with the card reader and how did you solve them?
I know this are many questions, but it would help me a lot if I can get my card reader back to work (there are some nice progams on the cards ;-) ).
Thanks a lot in advance.