Turned pulley regularly but more than necessary (6)
I believe the answer is:
unduly
'more than necessary' is the definition.
I can't tell whether this defines the answer.
'turned pulley regularly' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'turned'+'pulley'='turnedpulley'
The alternating letters of 'turnedpulley' are 'UNDULY'.
'but' is the link.
Can you help me to learn more?
(Other definitions for unduly that I've seen before include "To an excessive degree, improperly" , "Inordinately" , "Excessive, unjustified" , "Disproportionately or excessively" , "Excessive or unreasonable" .)