Comment # 4 on bug 857438 from Stanislav Brabec

Returning to the bug after the year because there was found a source of similar
problems that cause non-mounting of some USB drives.

According to the hwinfo, your disk has serial number "z".

It indicates, that something is wrong with the firmware of your drive. udisks2
tries to assign an unique name for the drive, and if the firmware provides
nonsenses, older versions of udisks2 can overflow.

Could you try:

udevadm info -q property /dev/sdb

/usr/bin/sg_inq --export /dev/sdb

/usr/bin/sg_inq --page=sn --export /dev/sdg

See bug 911898 for the whole thread about this problem. Your drive could have
the same problem.

Also syslog around the time of the connection would be interesting
(/var/log/messages in older distros and command journalctl in newer distros).