HP-65 more on the card reader

[albertofenini]

While repairing, it also happened us to break one of the contacts from the card reader to the main board.
Since it's a twin contact we hope this does not affect the functionalities of the card reader.
We tried to replace the gummy wheel with the following items :
- 2 traditional -o-ring
- 2 square o-ring
- only one square o-ring
- silicon tubing
In all of these cases we have not been able to record a single card.
Reading also is not 100% reliable
sometimes it reads all of the STANDARD PAC cards, sometimes it does not read on the first attempt,
but it will read on the following attempt
Sometime it reads, but when the program is launched it ends up in infinite loops with erratic results.
However most of the times it reads and it executes correctly the program.
It also can read cards recorded by the other two units we refurbished time ago.
When recording, it looks to us that the 00 00 digits will show up too early, when the card is still going thru the unit
We have also noticed that the noise that the motor does, it is different when the the unit reads a card fro when it try to records a card, does it make any sens ?
Lat, but may be not least, compared to the other units the card remains a little more inside the unit when read or recorded, like the motor was not able to pull it till the end.

Here are two Youtube links when the unit is reading and try to record

RECORDING https://www.youtube.com/watch?v=QAE8FesBPiI
READING https://www.youtube.com/watch?v=BjJuevQv6h0

What can we possibly try to get the machine more affordable in reading and successful in writing ?
We have already tried tens of different position with the eccentric cam without noticing any improvement