Jeep I6(242) E-Fan Swap

[DifferentPointofView]

Okay, so I didn't do this myself. But I did find out a DIY Post on a Jeep forum to swap out the mechanical fan for an electric fan.

The fan operates on an on-off-on switch, up if for high, middle is off, and down is low fan speed.

Not only does this benefit in quicker warm-ups, but since your mech. fan runs off belt speed, if you run low rpm's at highway speeds (i do) your Mech. fan isn't cooling off the engine efficiently if your going up hills and generating heat, but the belt speed is the same. This isn't much of a problem in the ZJ's, but for the TJ's and YJ's, their cooling system could use a bit more work.

With a full grille block in the summer, the temps can start to rise a bit, though I haven't seen temps over 200, could use a bit more cooling (oil temps are high and I'm getting low oil pressure from leakage). So if you are out wheeling or rock-crawling, and your giving your engine hell but the rpm's are in the low range, you need a cooling fan that can run on high, because your belt is making your mech. fan run slow. Well here's the DIY for an E-fan swap. It involves taking one out of a 3.8L in a Ford Taurus/sable/lincoln etc. Two bolts and you cut the wires.

http://www.jeepforum.com/forum/showt...ghlight=taurus

[SVOboy]

Nice find!

[Smoove]

I did the Taurus fan swap, and it required a ton of trimming to fit in the space alloted. It required a ton of power when it would start-up, and fried my DC controls controller.

I have been using a perma-cool 19115 16" fan and flex-a-lite variable speed controller for 6 relatively trouble free years.

This reminds me, I gotta put that Taurus fan on fleabay this summer, it has been in my in-laws basement since 2005!

[meemooer]

i did this last year before a weekend towing trip. I've towed the car to be towed back before, and i could tell it was one hellava difference. I gained i think 1-2mpg at the time. The biggest advantage was working under the hood. No worry about getting my hand in a blade, plus way more room, and changing the belt was so much easier.
ohh and i bought a kit for like $140 with a controller, wiring, fan, and whatnot, from a ranger online store. I'm happy

[Red]

About a year ago or so I did the swap on my TJ. I didn't really notice a major change in MPG or power. It was a cool gizmo though, but it does have a tendency to die when mudding. It did keep the coolant temps nearly dead on 207F no matter what.

Smoove, how'd you kill you DC Controller? Mine didn't suck that much power when it did a slow start up

[Smoove]

Originally Posted by Red

Smoove, how'd you kill you DC Controller? Mine didn't suck that much power when it did a slow start up

I loved it, and I would have bought another one but they are made in batches - and my wait time was around 5 months, which would have meant November wrenching.

Even on the slow start it would chug power, dimming the lights and causing an idle surge even though the controller was enabling the low speed only. I don't recall the exact numbers, but it was high. Since then fan only came on at traffic lights I eventually set up a manual override, which allowed me to kill the 12v signal to the controller if the light was about to change and throw the high side on as soon as I got moving.

[DifferentPointofView]

How much power does it draw? I run a 2400wPeak stereo with no problem unless i wanna hit high db's. By then my ceiling upholstery is falling apart and my mirror falls down and it points to the floor. and It causes my ears to ring badly. I don't know how much power a fan could draw.

[adam728]

I believe the Taurus fan can draw as high as 60 amps, and this is a constant load.

A stereo is rarely a constant load, unless you are just listening to sin waves at peak power (like doing burps at a competition). An amplifier that draws 100 amps at full tilt might only be hitting that number for 5% of the time during a song.

Also, 2400 watt peak means next to nothing, RMS wattage is what is meaningful. Lower-end companies like to use peak "if struck by lighting" wattages, where a "1000 watt" amp may only put out 100 watts rms. This is why something like my old 400x1 Rockford (bench tested 744 rms) would blow the doors off my friend's 900x1 Lanzar when we swapped it in. That 900 watt Lanzar was peak power, rms was 250 or 300 if I remember correctly, and even then, possibly over rated.

[DifferentPointofView]

I know about peak and continuous. It's rated at 1200RMS. I did it with a competition bass test. It's hooked up to 2 4ohm subs wired parallel. Its drawing around 1200wRMS at 14-14.4 volts.

I was just saying, if a burst at 2400 watts dims the lights, I was wondering how much power a fan was actually drawing.

[adam728]

We could also get into a lot of things with impedence rise based on the box size/design, specific subwoofer model, wiring configuration, frequency being played, etc, and find that you might only be putting a few hundred watts RMS into them and dimming the lights. Power thru a resistive load for rating purposes comes out much different than power thru a reactive load (speaker). A sub setup might be rated at 2 ohms, but you could throw it in a ported box, play a 50 or 60 hz sine wave and find that the amplifier is seeing something like a 12 ohm load. So that 1200 rms really only cranks 200 rms at that point. Because of box tuning, resonant frequency of the car, cancelation issues, etc, it might be louded at that particular frequency, even though a lower sine wave my put three times a much power into the subs.

If putting out a real-world-in-car wattage of even 600 rms, an 80% efficient (class D) amp at 14.0 volts will only draw 54 amps.

My long winded pointless point is that your stereo probably is not drawing nearly the power you think it is, yet can dim lights. So a large electric fan dimming lights on startup is not that surprising.