You certainly can motor a helicopter turbine to cool before fuel on. It's over 30 years since I last flew a UH1, but you could do so by running the starter motor with the twist-grip throttle closed.
In the Wessex, you could run the starter motor and chose when to "introduce fuel" by opening the HP Cock.
The Super Puma had a switch that basically allowed you to run the starter motor without fuel being introduced (memory fades even more here)
However, there is so much to be said for rotors-running refuels. Not least being that a "quick suck" of fuel will allow payload to be maximised, and need only take a few minutes.