HP-41 Card Reader

[n1msr]

I just got a USB re-chargeable LiPo battery for my 41CX from Diego Cruz, and was looking forward to using it to power the HP-41 card reader. However, the wheel was gummy - actually it had largely disintegrated. I looked at 3 or 4 sources online to learn what I needed to do, but after fitting o-rings for the wheel, the card reader doesn' seem to detect a (HP-67) card when inserted. I know that the motor and mechanism is OK because when I apply a low-ish voltage (~3V) to the motor terminals it runs and the magnetic card is pulled through the slot.

So I assume it must be the card detection that is not working. I read that the two narrow contact strips need to be aligned - I think they are but I have no way to tell if they really are other than seeing that they are correctly seated in the narrow channel and make contact with the small plastic pivoting pieces that they meet at one end.

The two copper "bowed" pieces look to be in place. The little plastic roller is also OK and in place (the bit that likes to skydive from the bench to secret places on the floor).

I am looking for a bit of guidance. I hope the above description makes sense.

(I would like to comment in passing that accessing the 41 card reader seems a whole lot easier than accessing the on on the 67!)

Thank you,

Mark