More chilly on board and they persistently find fault (8)

I believe the answer is:

scolders

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'they persistently find fault' is the definition.
The definition suggests an adverb but the answer is not.

'more chilly on board' is the wordplay.
'more chilly' becomes 'colder' (I've seen this in another clue).
'on' indicates putting letters inside.
'board' becomes 'ss' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'colder' put into 'ss' is 'SCOLDERS'.

'and' acts as a link.

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I've seen this clue in the Sydney Morning Herald.

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