New montage showing a small generator (7)
I believe the answer is:
magneto
'a small generator' is the definition.
(I've seen this in another clue)
'new montage' is the wordplay.
'new' indicates anagramming the letters.
'montage' is an anagram of 'MAGNETO'.
'showing' acts as a link.
(Other definitions for magneto that I've seen before include "engine part" , "car component" , "Car generator" , "Small electric generator" , "Small type of generator" .)