Hey all, just thought id post this for those interested.

the main thing i was focusing on with this was to make the install look as clean as possible, hide as much wiring as possible, etc. i think i achieved it pretty well.

First you gotta find a fan. they came in early 90s fords/mercurys with the 3.8 motor. picked mine up from the local junkyard for 18 bucks. when i clipped the wires, i clipped them after the factory connector, on the vehicle harness side. that way i still have the one connector if i ever need to remove the fan.
Next you gotta remove your clutch fan and shroud. you will need the fan clutch tool. if you dont have that (i didnt), you can use an air hammer to spin the clutch off. just get it right on the edge of the hex and give it a couple little bursts. should come right off.
next, i mocked up the e-fan.

next i worked on mounting it. took some thin steel strip i had and cut a couple pieces. dripped a couple holes in the fans housing and bolted it in to the stock fan shroud mounting points.

That was the easy part. now the wiring. since this is a 2 speed fan, you will need 2 separate relays. for the LOW setting (blue wire on ford harness), i used a standard 30 amp 4 pin relay. for the HIGH setting, i used a ford starter relay i grabbed from an expedition in the junkyard. its on the firewall on the passenger side in these. for the LOW setting, i used 10 gauge wire. for the HIGH setting, i used 8 gauge. i went to home depot and bought 8 feet of 10 gauge with the red sheathing, 8 feet of 8 gauge with red sheathing, and 5 feet of 10 gauge with black sheathing (for the ground). the wire cost me around 10 bucks. (you will have extra wire) for the trigger wires for the relays, i used 16 gauge. bought a roll at oreillys for 7 bucks.
first thing i did was measure out how much wire i needed and made a harness.

next, i mounted the big relay. i mounted it to one of the bolts that holds the fuse box bracket. this provides a good ground for the relay. youll need to remove your battery to get to this location. next i used a piece of the 8 gauge wire and connected it to one of the bolts that holds the + battery cable to the PDC. connected the other end to one side of the big relay using a ring connector.



next i set up the low speed relay. i just have it sitting in the corner by the battery tray. hooked a piece of the 10 ga wire from the PDC to the relay.

next i put in my wiring harness and make all the necessary connections. for ground i used the factory grounding point next to the battery

now we run the trigger wires to the switch inside the jeep. i used 16 gauge.
make the connections to the relays and run the wire along the firewall. i used some wire loom material so it looks better

heres where it goes thru the firewall

it helps to pull the washer fluid resivoir so you have room to feed it thru. be careful, the fluid will come out when you detatch the hoses. i had a bucket ready and just set the resivoir in it.
now fish em thru the other side

i mounted my switch on the switch panel i made to replace my VIC (vehicle information center). you can mount your switch anywhere you see fit. the switch is an ON-OFF-ON toggle switch rated at 16 amps i picked up for a few bucks at the auto part store.


thats pretty much it. throw your battery back in if you havent yet and flip the switch. if you see smoke, thats bad .

If you have any questions, feel free to PM me.

 

Looks like a well done installation, however I can suggest a couple of improvements. I think you should have the low fan run with ignition on. That way you can let anybody drive it without forgetting the switch. The changeover from low to high should be automatic thru a temp sensor. However the wiring gets a little complicated at this point. Your simple dash switch is a good approach.

My WJ has an electric fan that only runs on high when the temp gets to 205* and shuts off below that. I know when it's running because of a slight imbalance that shakes the steering wheel a touch. If it has a low speed, I've never seem it running.

 

if i had made it so the low speed runs when the ignition is on, i wouldve had to add another relay to turn low off when high is turned on. also, i wanted the option to turn it off completely if for some reason i need to work on something with the ignition on, so the fan isnt running and draining my battery. if someone else is driving the jeep, ill just leave the switch in low and tell them not to touch it. i wanted the simplicity of the switch rather than a sensor and all of its wiring.

I appreciate the input

 

OH! I forgot to add to the original post, I tapped the cigarette lighter outlet for power to turn the relays on. That way the fan will only run with the ignition on, so i dont forget and leave it running and drain my battery.

 

All good points and I appreciate your feedback. You are right about the third relay, also turning it off while working. I was thinking about my WIFE driving it! She once toasted my truck with a blown heater hose until it seized! It WAS night and it WAS raining, but still I had to tow it home. That was a sweet running 350 too, damn it!

I always thought it would be nice to have an ASD cutoff at 260*. IDK if Jeeps have this but it would be nice.

 

my dad used to be a service advisor at a Chrysler dodge jeep dealer. He had a 99 Durango that got towed in that the owners daughter fried the motor in. It was a nice one, leather, 4x4 the whole bit. My dad bought it from the owner for what the service bill was (which he discounted when he found out he was paying it) it might've been like 300 bucks. He sold it the next day to his mechanic buddy for 1000 and the mechanic put a junkyard motor in it and sold it for 3500

 

Mine cost me two pistons, one rod, a crank and a total rebuild, heads included. AND to never ran like it did before. I probably should have cammed it up, rather than use a new stock cam. I sort of got even because I had to drive her van to work until the truck was done. I was working on her brakes when she asked to borrow the truck and I said "Sure. Take it." Duh!

This was an 83 Chevy 350 4 bbl with no emissions except a cat. (4X4, 3.73 gears, NP 208 transfer, 33X12.5 tires)

 

You know, the nicest fan setup I've seen was an engine driven fan with an electric clutch like an A/C compressor. It was on a Peugeot (french car) my dad had. The engine only had about 90 hp and when the fan cut in, the car fell on it's face! No power left! It never overheated, though.

 

Update on this:
Do yourself a favor and buy brand new relays. i used junkyard ones, and the ford starter relay i used for high speed fan shorted itself yesterday and blew my cigarette lighter fuse.

 

At least you had it fused! I had fog lights wired to the power outlet (30 amp) and the relay trigger to the cigarette lighter. The only external wire I had to run was to the lights.

 

That's because they don't have a large duty cycle (They're not made for a constant draw). Even if you replace it with a new one it'll do the same thing. If you don't want to pony up for a 60A relay just run two 30A relays in parallel with each other.

 

I'm pretty sure that's not gunna work, dude. If one come in a nanosecond before the other, it will take all the load. I don't think you'll need more than 30 amps at the most. The things that kill a relay most often are contact arcing or holding coil burnout.