Try and eat earlier (4,1,2)
I believe the answer is:
have a go
'try' is the definition.
(to have a go is to make an attempt)
'eat earlier' is the wordplay.
'eat' becomes 'have' (I've seen this in another clue).
'earlier' becomes 'ago' (I've seen this before).
'have'+'ago'='HAVE-A-GO'
'and' acts as a link.
(Other definitions for have a go that I've seen before include "Tackle criminal" , "Words of encouragement" , "Attempt something" , "Take a turn" , "Make an attempt" .)