Bolt case after adjusting bar (8)
I believe the answer is:
obstacle
'bar' is the definition.
(I've seen this before)
'bolt case after adjusting' is the wordplay.
'after adjusting' indicates anagramming the letters.
'bolt'+'case'='boltcase'
'boltcase' with letters rearranged gives 'OBSTACLE'.
(Other definitions for obstacle that I've seen before include "difficulty" , "A spanner in the works?" , "hold-up" , "Anything that stands in the way" , "stumbling block" .)