LEGO Technic Unimog crane will not turn I finished the Unimog from LEGO 2 or 3 years ago, and I noticed this issue, but now I'm getting pretty angry because I still can't find the problem.  It seems to be that when I use the instructions for the function that should turn the crane, it doesn't turn.  All other functions work but unfortunately the turning, one of the coolest functions, does nothing.  Any recommendations?
When rotation / movements is blocked in a pneumatic set, this is often caused by the routing of the hoses. 

Remove the crane and check if its possible to rotate the crane by hand. If not, check if the hoses have enough slack to allow movement, or try the re-route them again.