Look no good for years (4)
I believe the answer is:
long
'years' is the definition.
(thesaurus)
'look no good' is the wordplay.
'look' becomes 'lo' (archaic exclamation meaning 'look!').
'no good' becomes 'ng' (abbreviation).
'lo'+'ng'='LONG'
'for' is the link.
(Other definitions for long that I've seen before include "extended period" , "Really want" , "Protracted" , "die" , "Extensive - pine" .)