Lotus Elan

generator w/ elec. fan?

PostPost by: rdssdi » Thu Jul 08, 2010 8:55 pm

I was wondering if anyone has installed an electric radiator fan and kept the original generator. At idle with the fan running is there an excessive current draw on the battery? Will the battery be drained in a short time?

I assume if there was air conditioning or headlights on that would increase the load to an excessive amount.

Is there any output from a generator at idle?

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PostPost by: Tonyw » Fri Jul 09, 2010 1:25 am


Generators do not produce much if any juice at idle, at best generators only put out about 22amps when fully operational, this is why many choose to make a sensible modification and put in an alternator.

If your fan is on in traffic you can be assured that your battery will be discharging.

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PostPost by: Frank Howard » Fri Jul 09, 2010 3:18 am

rdssdi wrote:I was wondering if anyone has installed an electric radiator fan and kept the original generator.

My car and many others came from the factory with an electric fan and a generator however that doesn't mean I recommend this combination.
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PostPost by: 69S4 » Fri Jul 09, 2010 6:16 am

As others have said that was a std factory set up and I had it on my S4 until I changed to an alternator last year. Many years ago I fitted a voltmeter to keep an eye on what the battery was having to put up with and, during the dynamo era, it was down around the 11v area with the fan on and the engine idling. Add in the lights, wipers etc and you'd better have a good battery.

I measured the current draw of the fan at around 8 amps. The lights will take another 10 amps, plus another 8 amps for the wipers if it's raining, so in a traffic jam on a wet night it's debatable whether the overheating or a flat battery is going to get you first :lol: :lol:
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