I see your error code----- Writing lastMountVersion as FSK
I've seen that before and it's discussed here a bit
http://www.sooperarticles.com/technology-articles/data-recovery-articles/how-res olve-mac-journal-magic-bad-error-340304.html
MAC operating system has a feature of journaling the file system due to which the chances of fault flexibility together with providing protection to the file system preventing from the hardware failure incidents and sudden power turn off. The journal plays vital role comprising all the confidential information that are required by the MAC operating system so that it could be returned to the previous working station.
These journals being vital component of the MAC operating system if gets corrupted, leads into serial results. It may turn the whole data inaccessible by means of turning the volume unmountable. Once user undergoes such disaster the only thing that leads to recover the situation is the valid backup as the data can be restored and the corrupted can be removed from the hard disk without being worried about the data loss issue.
While the corruption is encountered in the HFS volume of the MAC operating system then error that is encountered with the user is stated below:-
HFS(3): Journal replay fail. Writing lastMountVersion as FSK!
jnl: is_clean: journal magic is bad (0x1fd17 != 0x4a4e4c78)
HFS: late jnl init: failed to open/create the journal (retval 0).
jnl: open: journal magic is bad (0x1fd17 != 0x4a4e4c78)
While the corrupted HFS + volume is attempted to be mounted, the above shown error triggers on the screen. The corruption of journal being the major cause turns often turns to smash up the entire MAC volume to an extent along with damaging the command line. Although you may find the disk utility option as well as the command line application facilitated in the MAC operating system which you may use in order to get the issue resolved. If possible try disabling journal and further turning it on.