A French funny man, keeping working, making no money (10)
I believe the answer is:
uneconomic
'making no money' is the definition.
'a french funny man keeping working' is the wordplay.
'a french' becomes 'une' ('a' in French).
'funny man' becomes 'comic' (I've seen this before).
'keeping' is an insertion indicator.
'working' becomes 'on'.
'comic' placed around 'on' is 'conomic'.
'une'+'conomic'='UNECONOMIC'
(Other definitions for uneconomic that I've seen before include "Unprofitable" , "losing money" .)