MY build thread...'88 Bronco II Desert Rat Patrol Edition: MAJOR update 2/23/2025

[Peter Griffin]

After a parts mix-up I got the proper axle pivot drop brackets from Skyjacker and got those installed along with an alignment. With the radius arm drop brackets (and 2.5 degree camber bolts) that got the caster and camber, which was way outta whack, in check. Doesn't look all pigeon toed and wonky and tracked on the interstate just fine...

Sooooo...you know what that means!

Fix one thing and another goes south. It's was 115 when I was driving back and the temp get higher, the A/C weaker and the truck struggling to maintain speed. Fortunately it was a short enough trip and I got it home safely, at which point I jumped back on here and started following up on @PetroleumJunkie412 and @85_Ranger4x4 e-fan threads...

So I grabbed a set off of eBay and knowing I needed a way to RELIABLY wire them, I bit the bullet and went with a Dakota Digital fan controller.

Keeping in mind that I'm quite obvious a dilettante when it comes to this stuff I was hoping to get some help from y'all in getting it wired up.

It needs to be installed in the cab so I need a 12V and ignition source which I figured I could tap from the fuse box.

As far as the A/C switch, I was pretty sure I can tap it here up on the compressor, just need to figure out which one:

For the temp switch I thought I needed to tap this right about the water neck/thermostat housing:

The fan controller is insanely versatile and programmable via BlueTooth/app. I was fairly certain that the fans were only on/off and NOT dual speed, and with that being said, a 180-degree thermostat and some of the highest ambient air temperatures CONUS (literally only Death Valley gets hotter than where I am! ) I was curious what y'all think I should use for on/off temps for the two fans...?

Thanks is advance for the helpful replies, I appreciate...and desperately need it!

 

[Peter Griffin]

Ugh, apparently I have to use one of their (Dakota Digital) temp sensors...not sure which of these is the correct size...?

Water/Oil/Trans Temperature Sender

Dakota Digital manufactures digital instrumentation and accessories for the automotive, motorcycle and car audio enthusiast.

www.dakotadigital.com

*edit: Dakota Digital tech support was kind enough to let me know it's a 3/8ths and recommended their corresponding part number to go with it, so I'll grab that before I start tackling that install...!

 

[lil_Blue_Ford]

Well, I discovered today that my front axle shafts are roughly 2” too long on the passenger side on my Choptop, so chin up, you’re getting it there, lol. I, however, have a problem… lol

 

[Peter Griffin]

My MB dual e-fan pusher setup is here from eBay along with the Dakota Digital fan controller, just waiting on their temp sensor to have everything I need for the install...not that I couldn't start it mind you, which I'll be doing either today or tomorrow, but anyway!

I got the soundproofing mat installed on the roof, tailgate and sides. Easy enough to cut up and apply, just a lil time consuming...

I got the floor Raptor lined and will soundproof/mat that next before laying down the new carpet which has it's own insulation.

I've painted some of the interior pieces and finished up the dash which came out great except for the gauge cluster overlay which I painted semi-gloss black, had some small defects which I sanded out and came out a lil better...I'm sure I'll have at it again at some point!

The Coverlay dash cover install was a show. When I mocked it up it fit fairly well considering it's a 35 year old dash but there were definitely gaps where the factory color was going to show through. They include the silicone adhesive and after running a near perfect bead for what was maybe 20% of what I needed the back end of the tube split wide open and blew about half of the tube out in a gigantic blob. I frantically applied with my finger, a pocket knife and several other ad hoc/impromptu implements on my dining room table, which despite my laying down an old towel still managed to end up on it, much to my wife's chagrin.

Once the adhesive was on as best I could get it I laid it over the old dash, where the lower corner by the HVAC controller is would NOT lay flat and kept popping off. I ended up using a storage tote and a 1.5 poop kettle-bell (for all my CrossFitters here!) to put pressure on it while the adhesive set.

Coverlay says to use painter's tape to hold the overlay in position while the paint cures, which was worthless. I was using high quality 3M tape and it would not stick, never mind hold anything in position, so I opted for Gorilla (duct) tape which I knew may be a risky proposition...and it was somewhat...

The Gorilla tape held the dash down in position all right, and of course left adhesive on the overlay despite my best attempts at removing it slowly/carefully, but when the truck is sitting in 115-degree direct sun, stuff is gonna happen.

In addition to leaving adhesive reside it also pulled off some of the paint. It was VERY small and hardly noticeable, but I notice it of course! While cleaning the residue off with WD-40, which is hardly harsh/abrasive when used with a microfiber cloth, I was definitely getting some paint with it so I proceeded VERY carefully.

I finally installed a tan dash mat over the top of the dash. While it doesn't match the dash overlay it hardly matters as the vehicle stock used several different shades of brown/tan/camel and I definitely did not want a black dash mat.

Overall, including my white gauge face with blue LEDs, the look of the entire dash/instrument panel has dramatically been improved/updated, and it's a solid 90%+; not perfect but this isn't a professional restoration either in case you haven't been paying attention!

 

[Peter Griffin]

So here's how the dash and Raptor liner floor pan came out:

A keen eye will pick up @Jim Oaks USB charger in place where the cigarette lighter was...

 

[Peter Griffin]

Sooooo I went to install the dual Mercedes Benz AMG dual pusher e-fans that @PetroleumJunkie412 and @85_Ranger4x4 helped convinced me was a good idea for additional cooling in the extreme SW AZ temps I'm experiencing...

It was evident pretty quickly that it wasn't exactly going to be a drop-in. I cut off the side mounting brackets to give me some wiggle room but with my A/C condenser and radiator in place it wasn't going to happen, and I didn't want to evac my A/C system and drain my coolant...not being impatient or anything, but figured there was a way to make it work...

I ended up separating the fans which are joined by a bracket. That allowed me to easily fit the fans as shown in the picture:

Please note at this point the fans are NOT mounted. My plan is to move the driver's side fan up slightly, about even with the top edge of the condenser. Additional, as you can see from the oil cooler lines, the outboard line is close to the fan motor so I'm going to piggyback it on top of the other line with zip ties to give it plenty of clearance.

They'll be held in place from the same type of radiator/cooler zip mounts through the mounting holes. I'm also going to cover the contact area of the fan body which lies on top of the condenser with speaker gasket type material so it doesn't chap/rub the condenser.

I did a quick test (again) and ran them off the battery and it sounded like a Harrier jet on the flight deck! I'm thinking I might just wire them together (the stock wiring harness connects them together) instead of separately, at least for starters.

Question though...should I still run the stock engine fan? I was thinking no, but I want to see how it's going to do in these extreme temps. These fans are good for 3K CFM each, which together is about quadruple what the stock fan can move for air. I'd like to delete the fan if for no other reason than it massively reduces the drag on the engine, which isn't exactly a powerhouse to begin with!

I also need to figure out the fan on/off temperatures. I have a 180-degree thermostat in there now so suggestions for that are likewise appreciated!

 

[Jim Oaks]

Looks good!

 

[85_Ranger4x4]

I still have a low profile flex fan driven by the belt with mine. Without it the fans run quite a bit which I felt was a bigger drag on the engine than the flex fan.

Puller fans are more efficient than pusher fans. The car those fans are out of has a puller efan to actually cool the engine, those are just fans for the A/C condenser.

But I have a bigger heat pump than you do...

 

[PetroleumJunkie412]

Sooooo I went to install the dual Mercedes Benz AMG dual pusher e-fans that @PetroleumJunkie412 and @85_Ranger4x4 helped convinced me was a good idea for additional cooling in the extreme SW AZ temps I'm experiencing...

It was evident pretty quickly that it wasn't exactly going to be a drop-in. I cut off the side mounting brackets to give me some wiggle room but with my A/C condenser and radiator in place it wasn't going to happen, and I didn't want to evac my A/C system and drain my coolant...not being impatient or anything, but figured there was a way to make it work...

I ended up separating the fans which are joined by a bracket. That allowed me to easily fit the fans as shown in the picture:
View attachment 96021
Please note at this point the fans are NOT mounted. My plan is to move the driver's side fan up slightly, about even with the top edge of the condenser. Additional, as you can see from the oil cooler lines, the outboard line is close to the fan motor so I'm going to piggyback it on top of the other line with zip ties to give it plenty of clearance.

They'll be held in place from the same type of radiator/cooler zip mounts through the mounting holes. I'm also going to cover the contact area of the fan body which lies on top of the condenser with speaker gasket type material so it doesn't chap/rub the condenser.

I did a quick test (again) and ran them off the battery and it sounded like a Harrier jet on the flight deck! I'm thinking I might just wire them together (the stock wiring harness connects them together) instead of separately, at least for starters.

Question though...should I still run the stock engine fan? I was thinking no, but I want to see how it's going to do in these extreme temps. These fans are good for 3K CFM each, which together is about quadruple what the stock fan can move for air. I'd like to delete the fan if for no other reason than it massively reduces the drag on the engine, which isn't exactly a powerhouse to begin with!

I also need to figure out the fan on/off temperatures. I have a 180-degree thermostat in there now so suggestions for that are likewise appreciated!

I have mine on a dash switch for uh... 2.9 emergencies.

Often unnecessary. But good to have.

 

[Peter Griffin]

Thanks for the responses gentlemen, I appreciate it!

Worked on getting everything mounted "properly" (at least for now, hopefully permanently!) before starting on the wiring/fan controller.

Since the e-fans were going to be right on top of the A/C condenser, I put foam/speaker gasket material on the larger mating surfaces:

I got the foam insulation back in too (pictures are shown prior to the radiator being bolted into place). I'm pretty sure it's 2-inches thick and the radiator compresses it tightly so I'm getting a good seal to prevent air from blowing out of the sides. I didn't take a picture of it from underneath, but it does have that rubber seal at the bottom of the radiator (which you can kind of see at the bottom of this picture).

The e-fans were installed with the same plastic zip tie mounts that I used for my universal fan shroud creation. The way they fit in the radiator support and captured by the A/C condenser seems to REALLY have them in there solid. I didn't want any metal, etc. crushing or anything but suffice it to say I'm satisfied with the manner in which they're mounted.

The driver side fan is flush with the top of the A/C condenser. I could have mounted it higher where it would have exceeded the top of the condenser and was inline with the radiator but it would have been blocked by the sheet metal/radiator support, so I thought that was a balanced way to handle that side.

The passenger side fan rests on the lip of the radiator support on the bottom and on the side the flat side of the fan's mounting bracket is likewise flat against the side of the radiator support, which is solid. The fan obviously exceeds covering the condenser, which is fine with me, I'm certain that this combination of fans (and their rated output of 6K CFM combined) will dramatically increase the airflow I desperately need!

Not only did this staggered fitment work well for me, by positioning the passenger's side fan low I didn't have to relocate or otherwise deal with the oil cooler, with the minor exception of piggybacking the lines with zip ties to prevent any interference with the driver's side fan.

I fired them up for another test and man do they scream! I was using pretty thin gauge wires (16 maybe?) to connect them to the battery and my delight was interrupted by the wires obviously starting to warm up! I have separate 30-amp fused links and Dakota Digital's relays that look like they're wired to start a cruise ship, and I'll likewise make sure to wire up the rest of it properly; these fans are going to be working their collective arses off this time of year!

I definitely agree that pullers are better than pushers but likewise feel that two smaller fans are better than one big one...I think the stock fan is 14-inch diameter and these are 10-inch a piece. I may have been able to fit a large single fan in there but no way was it going to be 20-inches! With that being said I would like to be able to delete the stock fan but I'm not the far along in the process yet to know if that's a viable and reliable option.

I also MAY have to go down the upgraded alternator road, as I mentioned before with my first go round of the weak sauce fan that came with the Alloy Works radiator. I'm fairly certain I have a 85A alternator, and while I haven't done the electrical math yet but I'm optimistic that the amperage I'm "saving" by going all LEDs will help offset the demand of these e-fans and the powered subwoofer I'm using...

Wish me luck, I'm gonna need it! Thanks AGAIN all for your help...

 

[Peter Griffin]

OK...thanks to some wiring assistance from @Uncle Gump I got the Dakota Digital fan controller wired up.

I initially was getting an error code and false readings because I had tapped the sender wire from their coolant temp sensor with the factory temp sensor sender wire, which caused some kind of ground fault and screwed up the readings for both the Dakota Digital app and the factory coolant temp gauge. As soon as I disconnected it the Dakota Digital app displayed the proper temp, but my coolant temp gauge was obviously not working.

It was 113 here yesterday and dang near peak temps so I took it for a ride and it took forever for it to get over 200, and once it did it very slowly crept up to 206 and stayed there for as long as I was on the interstate.

Once I got off the interstate and started hitting local traffic the temp started creeping up more, and the A/C started working a little less, but the air it was putting out was still cool, but not cold. Both e-fans were blasting and I got up to 214 before stopping for an extended idle test.

Parked in the direct sun the temp slowly crept up and within 5 minutes was up to 227 (see picture). At that point the A/C was blowing air like that was almost heater-like. It wouldn't go any higher no matter how much longer I let it idle, so I shut it down and let the fans spin for an additional minute (I can set it for up to 3 minutes max with the engine off I believe, I'll have to check the app).

Since the factory gauge isn't working I don't know where that would correspond on the gauge sweep but I'm fairly certain that considering I was right between the N/O of the "NORMAL" on the gauge, I was definitely running "cooler" than that, so the e-fans are a win in my opinion.

With that being said, with a 180-degree thermostat I'm thinking my fan on/off temps are good (default) but I'm open to suggestions. The Dakota Digital fan controller also turns the fans on with the A/C regardless of engine temp and that feature works properly and likely the reason why it took a while to get up to temp yesterday since I turned the A/C on immediately.

Since I had to use the Dakota Digital coolant temp sensor with their fan controller, I'm still left with my coolant gauge dead in the water. It's pretty cool to be able to monitor the EXACT temperature with the app, but after all of the work I spent of the gauge cluster I'd REALLY like to get it work again.

I thought that @Uncle Gump or someone was saying that the sensor shown below with the red arrow also contains an engine coolant temp sensor for the "brain box" and I was trying to figure out if that's the case if I could maybe run the factory coolant temp gauge off of that...? You can also see the factory temp sensor line cut/disconnected next to the Dakota Digital sender/wire...

One other issue I've discovered is that the cruise control will not hold the speed once it's set...? It wasn't for a lack of power as I was on dead flat interstate and was able to maintain speed easily with the gas pedal so I'm wondering what that's all about.

I noticed that the transmission was "hunting" too and down and up shifting to maintain speed while the cruise control was off. I haven't yet serviced the transmission with a fluid/filter change (that's next week!), but the level and color are good and the shifts are solid. The speedo is reading about 5 MPH too low so I need to change the gear to correct that once I figure out what's in there now and what I need based off my tires...

 

[Uncle Gump]

I use one of these to run my aftermarket temp gauge. You can't run your temp gauge off the ECT. ECT is a thermistor and the gauge requires a variable resistor.

Cruise control could be a leaky servo.

 

[Peter Griffin]

@Uncle Gump, that slips over the radiator hose yeah? Would that work with the stock coolant temp gauge...?

I have to poke around and look into the servo deal...thanks!

 

[Uncle Gump]

It should go in the lower radiator hose according to the instructions. I also see no reason it wouldn't work for the stock sender.

 

[Uncle Gump]

I had to drill and tap a hole for a ground wire. Single pole sender would need the body of the sender grounded to work

They do make them with a ground lug too. I bought the wrong one.