Electric Fan installation - With Pics

[Number4]

I thought I'd post the information on my e-fan install for my 3rd gen 2004 Explorer with the 4.6l V8. I did this in March of 2014 I think, I really don't recall anymore. Unfortunately, I've lost some notes as well. So it'll mostly be pictures. A lot of pictures, so it may not view well on your phone.

I didn't land a Mark VIII fan and frankly I'm glad I didn't. I did get a fan off a Lincoln town car or something that had the 4.6l. It had an inrush well over the limits of my gauge (100+ amps) and I couldn't find a way to limit the inrush. I ended up with a fan out of a 2001 Mustang GT. The Mustangs inrush was just under 60 amps IIRC and ran at just under 20. If the fan was good enough for the 4.6 in the Mustang, I figured it had to work good for me. My Ex runs at 195 with the fan going (when needed.) On the hottest day in Atlanta, in the bumper to bumper traffic, the temp reached 212.

Mustang fan.

My cuts to the fan.

How the fan will set in the fan shroud.

Fabricated brackets to hold the upper portion of the fan in place. If I wasn't so lazy, I'd take these to someone and have them fabricate solid pieces. If I did that though, the fan still wouldn't be installed.

 

[Joe in NY]

for the a/c. you had it right the first time. think about it. If the compressor clutch is not engaged the compressor is doing nothing. If the compressor is doing nothing then no heat is being transferred. This is actually how all cars work. When the compressor kicks in the head pressure hits a certain target and the fan kicks on. Low side cuts out the compressor clutch and fan at the same time.

Our 2007 Suburban with dual electric fans on a cool day doesn't run the fans at all with ac on. Or when its winter and using defrost the compressor runs with no fans. Warmish days low speed cycling with the clutch. Hot days clutch just stays engaged and fans will cycle between high and low as needed (mostly high with 3 a/c zones )

And in the winter, with defrost (uses your ac btw) it is plenty cold that you will never need your fan on.

 

[Number4]

Biggest issue was the fan constantly cycling on and off. I found my AC wasn't very cold with it hooked up off the clutch cycling switch. Like than fan didn't stay on long enough to impact the refridgerant.

With the Flex a lite controller, the AC line feeds the fan at 60%. Using the rocker switch setup also gave me the ability to manually turn the fan on (at only 60%) when in stop and go or long lights. Otherwise, the fan would kick on, run for a sec till it cooled the engine, then shut down. Only to have the engine heat up again and come right back on.
So now, I can manually operate it as well it automatically comes on when the engine reaches 206.

 

[dieselscout80]

Looks like you did a great job.

Did it make your gas mileage increase at all?

 

[Number4]

Looks like you did a great job.

Did it make your gas mileage increase at all?

I have another post here that talks about my initial findings. The first few months showed an increase in my MPG. Using the odometer/tripometer vs gal used.

It's since gone back to 15.4-15.8. At first it was up around 16.7/8 or so.
I'm wondering if the computer needs to be flashed. Don't know to be honest.

I did it mainly for the project. Who doesn't like to tinker.

 

[Joe in NY]

if the fan is constantly running its putting a load on the alternator. therefore still a fan load on the motor. You will only see an increase during fall, winter, and spring when you dont run the ac and its cool enough out that no fan is required.

 

[Number4]

if the fan is constantly running its putting a load on the alternator. therefore still a fan load on the motor. You will only see an increase during fall, winter, and spring when you dont run the ac and its cool enough out that no fan is required.

The alternator spins relative to the speed and RPMs of the engine regardless of electrical demand. The regulator determines how much juice is let loose. With the fan and other accessories being on, the regulator will allow for greater output from the alternator, but it has no impact on the operational load of the engine.

Alternators aren't clutch driven like ac compressors are.

With a fully charged battery, the alternator is what's powering the car. It's electrical output passes right through a fully charged battery into the vehicle. At idle, when the RPMs are too low to sufficiently power the car, the battery becomes the power source. Once the vehicles RPMs increase, the alternator then replenishes the battery and resumes powering of the car.

All of this is controlled by the voltage regulator. The alternator itself will always spin, no matter the electrical demand as long as the engine is on.

 

[boominXplorer]

When I installed an E fan in my 01 ranger I tied my A/C turn on to the positive signal coming from the hvac unit. For my truck it was a violet wire that I was able to find in the engine compartment under the fuse box. My fans run all the time when the a/c is selected and even when it's 100* outside I can still get 34* air out my vents. I'm running a dual 2.5 v6 cougar fan setup.

My reason for the swap was controlabilty not fuel milage. I can turn it constant on, off (for water crossings) and there is a lot less strain on my water pump.

 

[Number4]

I did it because a deer took out my front end. Including the radiator and the fan blade. Well, the fan blade took out the radiator.

Your are lucky that your 01 isn't a CAN BUS system. Tapping into the signal wire for the third gen will interrupt the signal frequency and disable the circuit. I verified this with a lighted circuit tester. As soon as it was applied to the AC signal wire, the signal dropped. I was really really hoping it would have worked as it would have been the best option.

So now I press two buttons instead of one for ac.

 

[Joe in NY]

Number4, what are you talking about? Hook a volt meter up to the battery with the engine off and then start it. You will see the voltage go from around 12.6~12.8 to 13.6~14 volts. The battery ain't doing that by itself. The electric fan simply passes the load to the alternator. You people need to understand basic electricity. You all seem to think it comes from a battery which a fountain of youth. Put as many power hogging accessories as you want and it doesn't affect one thing... So I hook up a 1kW search light and leave it running for 2 hours at idle the battery magically supplies this? No. The alternator does. Also 1kW at 14 volts is over 70 amps. This will definitely put a load on the motor. Just as this 30 amp drawing fan does. So I hook up an electric a/c compressor, power steering pump, and water pump, I get free electricity from no where? No. The load is still there requiring the engine to put the same amount of effort in. Only now instead of belt driven it is converted to electricity and transferred over wires... All you are doing is changing the location of the load...

 

[Number4]

Everyone realizes the power is generated by the alternator. I don't see where anything was mentioned otherwise.
The alternator doesn't spin faster under a load. It spins relative to the engines RPMs. All that changes when an electrical demand is placed is the regulators output. A 130 amp alternator isn't generating a constant 130 amps. The alternator spins in relation to the engine and the regulator determines the alternators output.
If the regulator is putting out 10 amps or 80 amps, the alternator still spins according to the engine speed. The alternator doesn't change its rotation based on the electrical demand.

 

[boominXplorer]

What he is trying to say is the Alternator has parasitic drag which increases on load. You "technically" took most the load off the water pump pulley then increased the load on the alternator. I believe there is a benefit to it but some think making something more complicated for little gain isn't worth it........ I just like the flexibility of use.

 

[Joe in NY]

^^^^^^^^^^^^^^^

Bingo. Someone gets it. The more you draw on the alternator the more load it puts on the engine. It still spins the same rpm as it normally would yes. But it requires more effort to do so. All you did was take away the load from the water pump pulley and further increase the load on the alternator. Also, when the clutch fan engages it doesn't slow the motor down, it just puts a load on it. Just as if you shift into drive with the brake on. Now the transmission side of the torque converter is stopped, but the crank side is still spinning. Requires a lot of effort to keep the fluid moving vs having both sides spin the same rpm in neutral.

 

[Maniak]

As already pointed out.. An electric fan running isn't doing mileage any favors over a mechanical fan.. Both are putting a load on the engine..

The real difference is when the fan isn't running...

From reading this thread, it appears the newer explorers cycle the compressor much more which in turn would cycle the fan too. That is assuming you used the a/c clutch control wire to trigger the a/c circuit on the fan controller..

Since you guys are wiring it differently, you might as well make it so you can turn off the fan via the a/c control. In other words, wire it up so you can manually control the a/c fan trigger. You don't need the fan as your running down the highway (assuming your actually moving and not stuck in a traffic jam). By doing this you will get the gain of no load on the engine and since you hooked it to the a/c trigger on the controller if you forget to turn it back on for some reason when you are back in slow traffic the temperature control will still turn on the fan as things warm up.

While I haven't installed an electric fan on the newer explorers, the 3 vehicles I have installed them on all get a switch to disconnect the a/c compressor signal from the a/c fan trigger on the fan controller.

Keep in mind, I'm in the southwest US, where it gets hot and things are spread out so you can easily spend quite a bit of time at 70+mph in 105F+ weather.

~Mark

 

[Joe in NY]

The electric would be a benefit for me here in up state NY. Fall, winter, and spring are times that I dont ever need a fan. Its plenty cold and once you get going 25mph+ enough air is being forced through the radiator to not need a fan.

 

[Number4]

The 3rd gens can bus electrical system doesn't allow you to tap into the ac signal wire.

The alt rotor as I've stated rotates according to the engines speed.
The regulator in the alt determines the output and either increases or decreases the dc input to increase or decrease the magnetic field.
When the engine is at a higher rpm, the regulators dc input is lower and so is the magnetic field. At idle or lower rpms, the alternator applies more power and increases the magnetic field.
Now, the engine is burning gas because you are driving it. It's using fuel regardless of the ac draw on the alt. As the magnetic field increases at low rpms, it's "strain" on the engine is minimal. It's not an engine brake. A little gas powered generator would have a noticeable impact.
Now, your plastic fan, it's cutting thru the air at all times. Take a paddle and run it thru water, you get a lot of resistance. This is similar to the fans impact on the engine.

Whatever minimal "load" the alternator has on an engine, doesn't even compare to the load of the clutch fan.
You want to feel the difference?
Start your car cold with the clutch fan on. Listen and observe.
Then, remove the clutch and fan at another time for a cold start and observe.
You'll see the impact of the clutch fan.

 

[Maniak]

I think it is more power draw than you think...

When my mark VIII fan starts the inrush current it needs will pull down the RPMs about 150 rpm. When the fan starts it pulls about 60 amps startup and 30 amps continuous. I checked another one (a friends truck I did the e-fan install on) and his was closer to 50 amp inrush and just under 30 amp draw.

You may not think a 150 rpm drop is much BUT, this is on a 460 ci motor and I'm using a 90 amp alternator. There is definitely a load on the engine. Now is it as much as the fan clutch.. I can't do that kind of math..

~Mark

Edit: just to make it clear... I'm not bashing electric fans. I think they are much better than mechanical fans.. They will just help more or less depending on the driving situation...

 

[Joe in NY]

If your are moving 3,000 cfm with a clutch fan or electric, regardless you are moving 3,000 cfm. Thats a lot of work. So your saying a 10kw generator will run on 1 gallon of gas with no load just as long as it would with 5 kw load? No it wont. You are doing more work. More work needs more energy input. And the electric fan loses a lot of energy in heat. As electrons flow along the wiring there is friction in the wire and energy is converted to heat. It has to flow through the regulator, alt wiring, then the fan controller wiring, fan controller, fan wiring, and then the fan motor. There is a lot of energy lost in heat. Go ahead and start your motor with the fan motor at 100%. Then shut it off. I guarantee that you will gain 100 rpm's before the IAC compensates for the lost load.

Also, alternators are 3 phase generator with full bridge rectifiers for each phase that then pass through the regulator which creates a good bit of heat (energy lost) in lowering the high rectified voltage to the appropriate 14 volts.

So weather it be a clutch fan or electric fan it puts a good load on the motor. I mean when the dual electrics kick in on the suburban the motor slows down a bit and the voltage drops from 15.2 volts to 14 volts. And trust me, each fan in the burb is equivalent to the one fan that you guys are using for the explorers. Together they move a freaking lot of air...

 

[lincolnshibuya]

there's a misunderstanding on this and I remember reading an article from a mechanical engineer's opinion on the e-fan/clutch conversion. here's an explanation from the internet...

"The short answer is this, no matter what, if you apply more electrical load, the generator will use more fuel. Here is why. By the law of "conservation of energy", Energy can neither be created or destroyed. This means that the energy stored in fuel must equal the electric energy being consumed by your house, with some losses in effciency along the way associated with engine driven generators. The efficiency, or lack there of, at very light loads or at excessive loads will become more noticable, but never the less, if you use more energy in electricity, you will definitely use more fuel.
As for some of the other answers given. Just becuase an engine runs at a constant speed, does not mean that it is using a constant amount of fuel. In the case of a generator using a wound 2 pole alternator to produce power, it must run at 3600 RPM in order to produce 60 cycle current. But as the load on the generator (electrical) increases, the engine responds by opening the throttle to keep turning at 3600 RPM. When the throttle opens, it will allow more fuel to be consumed. This action is caused by a governor. All generator sets, big or small have some sort of governor. If they did not have some type of governor it would be imposible to maintain 60 cycle current under varying load conditions. There are some generators which will run at variable speed using a permanent magnet generator and an electronic device to simulate a 60 cycle syne wave, but they are still governed, and they will still use more fuel if more load is applied.
In conclusion, More power out means more fuel in."