Join Date: Jul 2001
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Re: Why electric fans?
Electric fans have their place when a mechanical won't fit or when water is an issue.
Electrics do not pull as much air through a radiator as a mechanical fan. Their CFM rating is a best case scenario (i.e. not pulling air through a restriction such as a radiator).
A shrouded mechanical fan with a thermal clutch is the most effective cooling strategy in most situations. Think about it....an electric fan is a fan blade driven by an electric motor driven by an alternator driven by the same belt as a mechanical fan. There are some efficiency losses in the energy transfer.
The thermal clutch normally starts to slip at about 1800 RPM - Higher if the air is hot. This prevents too much power loss at higher RPM.
1976 CJ7 304/TH400/QT/D30/AMC20
Front D44 in process.