An electric fanc does draw power from the electrical system, but not from the engine directly. It uses power generated by the alternator. The extra drag on the engine from the load on the alternator is much less than the drag from a belt driven fan.

Thermostatically controlled directly driven cooling fans are nothing new. My '69 Plymouth Satellite had one.

According to the FSM, the fans on our cars are mounted on a clutch that is controlled by temperature and engine speed. If the engine speed is low or the temperature felt by the clutch is high, the clutch engages to spin the fan. If the car is moving fast enough to move sufficient air through the radiator to cool the engine, theoretically the fan should freewheel, using little or no power. Practically, the fan will always use a little engine power to spin so it will pull air through the radiator. If it didn't, it would have no way to reliably feel the air temperature.

My '94 Suzuki Sidekick had an electric booster fan mounted between the grille and air conditioner condenser coil. It was a very shallow unit and operated when the A/C clutch was engaged or a high-temp switch on the thermostat housing opened (for fail-safe operation). Maybe you can find one on a Sidekick at a wrecking yard. I seriously suggest using a relay to control the fan motor and find a control power source that is hot when the ignition is on to keep the fan from operating when the ignition is off.

Don, y'all
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