In article ,
Steve Walker wrote:
When a car is moving, the airflow through the rad means a decent
viscous coupling is going to waste a tiny amount of power, unless
needed to cool things. And when needed (like say when stopped or
moving slowly, is an electric one going to be any more efficient?
After all the same belt drives the alternator which feeds the electric
motor.

Viscous fans disappeared from most cars in the '90s.

You'd have to define most cars. Still in use in the last decade, if not
now. Unless you mean the simple viscous coupling that only restricted the
maximum speed. They were old hat in the 70s.

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*Any connection between your reality and mine is purely coincidental

Dave Plowman London SW
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