Electric Fan fix-up.

Red

Member
The previous owner installed an electric fan out of a Saturn Ion but he wired it up with only a manual on/off switch, which I hate because I have to constantly watch the temperature guage and turn it on and off in traffic.

So I went to a shop close to where I work and had the guy take a look at it to see what he could do and he said he is going to install a sensor/switch kind of device in the bottom radiator hose that will turn the fan on and off depending on the temperature of the coolant.

Does this sound like the correct way to do this to you more experienced guys?

I know alot of people that do the Taurus fan mod or the flexalite one use a type of probe that is inserted into the veins in the radiator but the guy at the shop told me inserting this sensor/switch into the bottom rad hose is the best way to do it.

Any suggestions or tips would be appreciated.

Also, the fan is from a Saturn Ion I was told and it looks like he just trimmed both sides of it and its exactly the same size as the radiator so it seems to work well. I have yet to have it out in the wamer summer temperatures.
 
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Red said:
The previous owner installed an electric fan out of a Saturn Ion but he wired it up with only a manual on/off switch, which I hate because I have to constantly watch the temperature guage and turn it on and off in traffic.

So I went to a shop close to where I work and had the guy take a look at it to see what he could do and he said he is going to install a sensor/switch kind of device in the bottom radiator hose that will turn the fan on and off depending on the temperature of the coolant.

Does this sound like the correct way to do this to you more experienced guys?

I know alot of people that do the Taurus fan mod or the flexalite one use a type of probe that is inserted into the veins in the radiator but the guy at the shop told me inserting this sensor/switch into the bottom rad hose is the best way to do it.

Any suggestions or tips would be appreciated.

Also, the fan is from a Saturn Ion I was told and it looks like he just trimmed both sides of it and its exactly the same size as the radiator so it seems to work well. I have yet to have it out in the wamer summer temperatures.

Yes, adding the temp switch is the right answer. Ideally the temp switch would have some adjustability to it so you can fine tune it as you gain experience with it.
 
Thanks,
I'll see if the switch has any kind of adjustability, If it isnt adjustable, what kind of temperature setting should the switch have? is the OEM thermostat 190 degrees? I am unfamiliar.

Hopefully the guy ordered the correct switch
 
I don't know if it's 190 but that's probably close. The bottom hose is the "to-the-engine" hose. Assuming it 190 you probably want the fan to trip on at 160-170 would be my guess.
 
So would the bottom rad hose be the best one to put the switch on? the sensor will be reading the temperature of the coolant after it has been cooled in the rad, would it make more sense to have the switch read the temperature of the coolant after it has cycled through the motor?
 
If it's 20 degrees out and the T4R is warmed up the top hose will be spitting out 200 coolant. If it's 80 out the top hose should be spitting out 200 degree coolant. (It usually runs about 7-10 over the t-stat rating). If it's 20 out by the time the coolant gets picked up at the bottom (even with no fan running) it'll be plenty cool. When it's 80 out the radiator may need the assistance of the electric fan to cool the fluid.

You could put it on the top hose but IMHO, the bottom hose is better as it provides all of the necessary cooling and minimal fan use.

Many people go to electric fans to reduce parasitic drag. If you run the electric fan all the time there's little reduction as the alternator has to produce that electricty. The more you ask of your alternator the harder it turns.

:cheers:
 
Ah yes, ok that makes sense.
Well, Im just waiting for the part to come in and then im going to take my 4runner back to the guy and have him wire the switch into the bottom Rad hose, hopefully this all goes smoothly without any "hiccups".
I still havent had the electric fan mod during warm summer weather so hopefully the fan itself can keep up. If not I'll have to go back to the clutch fan or maybe try the Flexalite kit.
 
The elec. fan will most likely do fine.

I have replaced the stock belt driven fan with a junkyard or universal electric fan on every vehicle I have owned that did not come with electric stock. Has always been great to free up a little power and gain some MPG.

I usually use a universal thermostat that goes through the radiator. Like this: http://store.summitracing.com/partdetail.asp?autofilter=1&part=DER-16759&N=700+115&autoview=sku

This has always worked great for me as I can adjust the fans to come on earlier when I am putting the vehicle under load (like roadin or racin). I notice with most vehicles that the fans really only come on when sitting in traffic or moving very slowly. When the car is moving there is plenty of air going through the radiator.

The way the previous owner modded the shroud/fan combo sounds about right. As long as the shroud covers most of the radiator to pull air from front to back (not through the sides) you will be all set.


Also... the best thing you can do for your cooling system is flush it regularly. At the very least every 2 years.

Good luck.
 
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How important is it for the shroud to be covering the new electrical fan? I have heard of people just placing the electrical fan up against the radiator without a shroud, but am wondering if this is a good idea or not?
 
Anglr200 said:
How important is it for the shroud to be covering the new electrical fan? I have heard of people just placing the electrical fan up against the radiator without a shroud, but am wondering if this is a good idea or not?

It depends on the climate you are in and whether or not you are going to be doing a lot of low speed driving or towing.

If you are somewhere that rarely gets over 80 degrees it is probably no big deal. If you are somewhere where it routinely gets above 100 degrees and will be sitting in traffic it could be the difference between cooling down and overheating.

It also depends on how many CFM the fan pulls. If it is a high enough volume fan it could overcome this. I have no idea what CFM it would need to be, but it would be a big fan that would take up a lot of juice. For comparison the fan in the shrouded flex-a-lite kit is 2,800 cfm.
 
Thanks Tehdago,
Where I live the average year round is in the low 60s or high 50s, so it is probably not much of an issue. Im thinking about buying a less expesnive fan and then "modifying" my shroud to fit around it. This will put my mind at ease when I go traveling to hotter climates.
 
Thats definitely a low cost option. I have done a single 16" fan that fit snugly in the shroud of my olds, and it kept the 455 v8 cool all summer. :D

I would recommend dropping the extra $30 to get a fan controller. So you don't have to babysit the temperature all the time and deal with a toggle switch.
 
I got my truck back last friday but the guy at the shop didnt buy the right fan controller switch. Im not sure if he know whats hes doing. He tried to use some type of sensor that just wraps around the bottom rad hose. He couldnt get the switch to work so he's going to try again with a different type of switch.

So It seems alot of people just use the adjustable fan controller that has the radiator probe to read the temperature.

If I use that, what temperature should I try to set it at and where should I locate the probe in the radiator? near the bottom rad hose?
 
I usually set mine to around 190 or so... You will not be able to set it by temperature. Let the truck Idle up to operating temperature (just a little over 1/2 way up the gauge) then turn the rheostat (knob) on the controller until the fan comes on. Let the fan cool the truck down and make sure it comes on again when the truck reaches temp.

I'd also recommend running a wire from the AC clutch to the relay that controls the fan so that it will come on whenever the AC compressor kicks in. I don't know what wire to tell you to use since I haven't dug into my truck yet, but I am sure it is documented somewhere.

You also want to mount the thermometer probe just after the thermostat so it reads the temp of the hot coolant exiting the engine as opposed to the cool coolant entering. IIRC that would be the TOP radiator hose on the t4r.

Here is a good article with a wiring diagram I just googled. It may help if you want to take a shot at fixing it yourself. Good Luck
http://www.fordmuscle.com/archives/2003/02/electricfan/
 
So Im tired of waiting for the guy at the shop to order the right parts, he tried to use a fan controller that wrapped around the bottom rad hose or something like that and that didnt work, which I kind of suspected it wouldnt.

So I ordered this part from Streetrodstuff.com
I just searched the net and found one or two sources for a part like this and chose this on, im sure there are better deals out there but whatever.

-Adjustable activation screw sets fan activation anywhere from 150
 
Looks good. Thats similar to what I used to control the dual fans on my Olds.

On the 4runner I got lazy and used the Flex-A-Lite kit. Which is pretty nice. I had a couple issues with it, but nothing major. It uses the same kind of probe and relay setup.
 
i have my sensor about 1/3 the way up from the bottom of the radiator and it has constant power (will run with the ign off) to prevent engine "soak."

As for putting the sensor in the top hose thats a bad idea for what you want it for (mileage) and even just general use..

it will turn on as soon as the engine is warm and run constantly sapping power..

if you set it so it doesn't run constantly then you engine is getting hot coolant into the engine...

at the bottom of the radiator (or near the bottom) it will only turn on when the radiator is all hot (feel the radiator it will be hot at the top cold at the bottom) if cold water is coming out the bottom then why have the fan on? if its hot then turn her on..
 
My probe is right next to the top radiator hose. My fan doesn't come on until the temp is around 215 or so. Mine is also on an adjustable controller so I can make it colder or hotter.
 
but that doesn't change the fact that its testing coolant before the radiator has done its work on it instead of testing on the way out to supplement the radiator..
 

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