[DoubleJ]

I know I'm about 15 years late to the party, but figured I'd lay out how I put an electric fan in my Dakota the other day.

First, take out your stupid, noisy, dumb, loud, MPG destroying, power robbing, constantly running even when it's not hot out engine driven "clutch" fan and go make a Chrysler engineer eat it.

Then, get on ebay, and buy an electric fan for a 1999 to 2003 Grand Cherokee. That's right, buy a fan from an older model Chrysler vehicle to replace the ancient turd in your slightly newer Chrysler vehicle. Make sure you also hit a junkyard or something and get the connector for it. I found one locally, but the GC had a hydraulic fan in it for some reason, and the connector I got was wired up with like 16g wire, which had to be replaced with 10g wire.

To fit the fan in the truck, and I forgot to photo this part, remove your upper shroud, and use a dremel to cut two slots in your lower shroud for the two lower tabs on the fan housing. Measure 8 times, cut once, or your fan will be crooked like mine. My truck will probably pull to the right on the highway now.

For the upper mounting tab, I made this hokey bracket, but it's solid.

So now your fan is mounted. Easy part is done.

 

[DoubleJ]

Now you gotta wire this bad boy up. You need a big relay, and a way to turn the relay on. I chose to let the engine control the fan instead of forgetting about a switch or something. You could also lower the temp of your AC fan with some computer tuner doodad, and switch the relay off that, but then you've got no fans or two fans. With this setup, I've got no fans, one fan, or two fans. Here's the monster 60amp relay mounted behind the fuse box under the hood.

Stole power from here, and put a fuse holder inline.

You'll need to carry that power from the relay to the fan, then find a nice solid ground for the fan also. Don't skimp that part, ground is just as important as power. The battery has a ground straight to chassis between it and the headlight. I don't have a picture, but just follow the battery ground to a body colored nut on a bolt. Here's the connector plugged in after I replaced the little wires with 10g stuff.

Now you got big power, and it's time for little power.

 

[DoubleJ]

For my switch, I found this 90/95 degree Celsius thing on ebay, 14x1.5mm threaded, think it's for a Beemer or something. The coolant bleed in your upper radiator hose is 3/8 NPT, which is the same as your toilet at home. Seriously. Hardware store had a 3/8 x 1/8 NPT bushing. Also needed a 31/64ths drill bit, and a 14 x 1.5mm tap, which was on ebay for $5.

Drill it, tap it, put it in. I sealed it with water pump RTV, needs 24 hours to cure. Don't use 2 stroke oil as cutting fluid. Use liquid wrench instead.

Now that circuit needs power. You could use battery power, but it'll run after you turn the key off, until the top of the engine cools, not until the radiator cools. Not a good plan. Here's a switched source for power in your dash mounted fuse box, isn't used for anything. Put a fuse inline here too, bad place for a fire.

Run that wire through your relay, then through your switch, then to ground.

Your done. I used my heat measuring gun, fan came on at either 196 or 202 depending on where I took the reading, but never saw the gauge in the truck get near 210. Hopefully it keeps up with summer and AC, I'll find out. Got a 25A fuse in the main fuse holder, and although the engine loads when the fan inrushes, the fuse didn't pop, so maybe all that 10g and 60A stuff was overkill. Again, I'll find out in the summer.

 

[DoubleJ]

Update after driving with this all summer: Works great. The location of the thermal switch is not ideal though if you have a coolant leak. Being the highest point in the system, it gets the first air bubble and on your first few heat cycles the fan will come on late. Once the system fills itself from the overflow, it works tip top.

 

[DoubleJ]

Update: The 25A fuse did pop, after like 2 years. I put a 30 in, so far so good.