Go and mend (6)
I believe the answer is:
repair
I believe this clue is a double definition.
'go' is the first definition.
(I've seen this before)
'mend' is the second definition.
('repair' can be a synonym of 'mend')
'and' acts as a link.
(Other definitions for repair that I've seen before include "Travel or proceed toward some place" , "Proceed - restore" , "Restore to working order" , "darn?" , "Maintain" .)