The points should be adjusted for this part of the engine (6)
I believe the answer is:
piston
'engine' is the definition.
(thesaurus)
'the points should be adjusted' is the wordplay.
'should be adjusted' is an anagram indicator.
'points' is an anagram of 'PISTON'.
'for this part of the' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for piston that I've seen before include "Block sliding in hollow cylinder in machinery etc" , "Sliding piece in a cylinder" , "Part of a machine with a plunging motion" , "Points about driving rod" , "Brass instrument valve" .)