I have a 1982 diesel to gas conversion.

A few days ago the odometer quit working.  The speedometer is working fine,
so obviously, the cable inside the cable housing is turning properly.  I
removed the instrument and, using a drill with proper square bit, spun the
instrument, and on the table, both speedometer and odometer worked fine, but
after I reinstalled everything, it was the same as before.

Any idea what is going on here?

Paul from Colorado