Well, I figured I would do a write up on my electric fan install using a volvo 2 speed fan relay, and a bmw 2 speed fan temp switch, with a ford taurus 2 speed fan. my truck is a 91 dakota sport with the 318 LA motor.


I picked up a ford taurus fan. you can find these in the jy pretty easily (at least around here) You can find the fan in the follow with the 3.8 motors.

FORD TAURUS GL (1992 - 1995)
FORD TAURUS L 1992
FORD TAURUS LX (1992 - 1995)
FORD TAURUS SE 1995
FORD THUNDERBIRD LX (1994 - 1997)
LINCOLN CONTINENTAL (1988 - 1990)
LINCOLN CONTINENTAL EXECUTIVE (1991 - 1994)
LINCOLN CONTINENTAL SIGNATURE (1988 - 1994)
MERCURY SABLE (1992 - 1995)
(Thanks crazy as i borrowed this from your thread)

Then i snagged a volvo 2 speed fan controller relay. I honestly dont know what i found it in, I just knew what i was looking for from a different thread i look at) You will want to make sure to get as much of the wiring and the harnesses at the junkyard for this relay.

this picture is of the fan controller (after installation) The relay wired next to it i wired on the hot side of the volvo controller (so that it cannot turn the fans on without the key on to prevent battery drain) (I have some other wiring to clean up as well from past projects)



Then i got a bmw two speed temp switch from the junkyard. Once again i just browsed until i found one unsure of what they are found in. here is a link to rock auto for the part new https://www.rockauto.com/dbphp/prt,107,61311378073
I snagged a switch at the junkyard to start the process and getting it set up/wired and order the rock auto one. I received the rockauto.com switch and it didnt work on the low side. If your more into buying local (easier to return exchange but a little more costly) i purchased another at autozone part number sw940. http://www.autozone.com/autozone/par...ing+fan+switch

It comes with a lifetime warranty. They may have to order it in, but i was lucky enough to find a store close enough that one.

The temp switch triggers low at 91C, high at 99C And is located in the side of the radiator in the bmws.

Other than that i got some 8, 12, and 16 gauge wire, and various crimps and heat shrink for the install. I got a 1/2 brass pipe t some barb fittings and a reducer to make the housing for the temp switch.

Now Ill go into the fan installation itself. I already had a dual fan setup so my clutch fan was already removed. I removed the radiator from the vehicle and made up some mounts for the fan. You can see how i mounted it in the picture (just be creative with some thin angle/flat stock and you can make it mount pretty easy)
please ignore my poor bends on the one piece of flat stock i ran out of new stuff and had to re-bend a piece i already bent for another project.


I then dropped the radiator back in and bolted it up. I had plenty of clearance. I also have a 2 inch body lift which im sure helped.




Next On to the fun wiring part.

I will start from the battery and describe how i wired it (sorry i dont have any fancy diagrams drew up for this)

I went from battery positive to a 50 amp circuit breaker. (8 gauge)

Output of circuit breaker to pin 30 on a 70 amp relay (8 gauge)

hooked pin 85 to ground (12 gauge) and pin 86 to a switched 12+ source. (12 gauge)

I then wired pin 87 to the plug labeled 30 on the volvo controller (8 gauge)

Then i wired the high side of the fan motor (wire colors vary depending on year make and model you get the fan from but test it and you can find out easily) to the terminal labeled 2 on the volvo controller with the heavier wire (8 gauge wire) Low side from fan motor was wired to the label 1 with heavier wire on volvo controller. The third wire (black) went to a good ground (8 gauge as well)

Now onto the temp switch, as well all know there isnt a good spot to add a coolant temp sender/switch anywhere in these motor. I used some ideas from a few people here and decided to splice into my heater line.

The temperature sender has m14x1.5 threads which was one fo the challenges in using this temp switch. I bough a brass 1/2 T and a pair of 1/2 x 5/8 barb fittings and a 1/2 to 1/4 pipe thread reducer. I then drilled and tapped out the 1/4 pipe threads to the m14x1.5 and worked like a charm. You cant see it well but under my plug wires is this brass sensor housing i made. Its right before the heater core.



Now to wire this switch in. Inside the connector on the switch it is labeled.
T2 goes to the number 2 pin on the volvo controller (high side) and T1 goes to the Number 1 spot (low side). The third wire on the harness goes to a good ground. I used 16 gauge for these since its a lower current demand.

Then i filled it up and bled the cooling system and waited for the fan to come on. Turned out my jy switch the low side is bad. At least i still get high! We will see how the set up really works once i get the new temp switch in.

(this is my first write up and i may have blabbed a bit here and there and seem repetitive) Any other questions or tips let me know. Im always open to positive criticism.

Im also going to wire in a bypass switch so i can trigger the high side on when i please as well a wire a dead mans switch so that the fan is completely off (good for water crossings and such)

Here is a couple schematics i borrowed from other forums. the one diagram says something about a audi/vw temp switch. they are another possibility but have larger threads (m22 i believe) i opted for the bmw switch but its the same theory)





Update: I figured out how to wire my deadmans switch and high side constant on. I purchased a 3 way on-off-on switch. which lights up green in one position, clear when off and red in the second on position. I wired the 12+ lead of the switch with a good ground,(as well as hooked the ground tab for the light as a 12+ switched) I ran the temperature switch main ground wire to the terminal for the green lighted side. when in this position the fan will work as normal cycling through off, low, and high as needed. Then I wired the other terminal to the wire coming out of the temp switch for the high side. When the switch is in this position only high side will run and it will run constantly. Of course when the switch is in the off position the temperature switch with have no ground signal to send to the relay so essentially the fan control will be disabled. I will see how this works out over the next couple of weeks and see if i need to modify this idea.

 

That's a nice write up! I might just use this on my 87 Cutlass. Could you get my some dimensions on the fans? Length, width, and depth, especially from the rad to the fan motors?
I installed a mark VIII fan (was for my cutlass but didn't fit, the fan motor hit the waterpump) on my 93 because with the plow blocking the grille, it wasn't getting much airflow over the rad with the stock fan. Now it never goes above 1/3 of the way up the gauge. I didn't go this fancy though. I just wired it to a relay and a toggle switch on the dash. When I start it or once its warmed up I flip the switch and it stays on. The thermostat opening and closing keeps the truck at a pretty steady temp even with the fan on constantly.

 

Over the next couple of days i can get some measurements for ya. My old fan system consisted of a dual fan setup from a grand caravan. It worked alright but didnt cool as well as i liked. I had it set with a cheap hayden controller with the probe thats in between the fins of the radiator and it kept burning the controllers out.

I think the taurus fan left me a much cleaner install. Plus with this setup i dont have to worry about forgetting to turn it on or the constant extra electrical pull.

Alot of people trim the shrouds on the taurus fan to make it a little thinner. Another option for a fan is a volvo 2 speed fan. If I recall, they move alot of air as well and are thinner.

 

Thanks btw! It was actually my first "how to" on a forum. I looked at so many forums and posts to figure out what i was going to do. Figured id slap it all together for anyone to get ideas from or copy. after all that is how i got all my information.