Light on old motor of aircraft, oft on the blink (11)

I believe the answer is:

trafficator

'light on old motor' is the definition.
(obsolete device once found in car)

'aircraft oft on the blink' is the wordplay.
'on the blink' is an anagram indicator (informal phrase meaning 'not working properly').
'aircraft'+'oft'='aircraftoft'
'aircraftoft' is an anagram of 'TRAFFICATOR'.

'of' is the link.

I've seen this clue in The Times.

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