If you could find a relay with 87a and no 87, yes. But that is not going to be easy to find since you're sourcing a relay that turns on power when the relay is turned off. There are undoubtedly some custom applications, but generally folks want a relay to carry power when the relay is activated, not deactivated. That is how pretty much every fan and horn and light relays work.

 

I did exactly this playing in some mud....Never again! Luckily the dealership replaced the fan under warranty so I didn't have to pay the insane price

 

Okay, here's some more information on the fan relay install. And, the diagram I drew up earlier was from memory. It was essentially correct, but I got the color of one of the wires wrong. I will correct that on my post above, and if anyone has quoted that, you might also correct it (or just delete the diagram from within your quote). The white wire is actually blue.

Overall diagram looking from the driver's side of the engine compartment across the back of the radiator ...


The blue and yellow wires go from the sPOD to the coil of the added fan relay ...


View of the added fan relay from the passenger's side of the vehicle. Basically I cut the black wire and added the terminal spade lugs to it that came with the new relay. I routed the blue and yellow wire from the sPOD to the coil of the fan relay--they use smaller ("normal" size) spade lugs. So, there are four wires there--the black (twice because it's cut in two), the blue (there are two blue wires, the OEM one bypassing this relay and going directly to the fan, and the in the picture that I added) and the yellow. A couple other zip-ties hold it all together, and it's been wrapped up in F4 tape. A third zip-tie secures the bundle to the fan shroud. I did it this way to avoid having to extend the black OEM wire to the fan to some other location where I could better mount the fan relay.


When the sPOD switch is off (down), the engine fan operates normally. That is, this switch does not turn on the fan. Rather, it allows the Jeep to turn on the fan when the Jeep thinks it's necessary--normally, OEM-designed operation.


However, when the sPOD switch is on (up), the engine fan cannot operate. It is forced off. Again, I know this works for the 3.8; I'm not sure for the 3.6s. If you have this switch on, the light turns on. The light being on means that the fan is off.


What happened to me the other day was a failure inside of that switch and whenever I'd turn on the panel lights (the little row of lights at the bottom of each toggle), some of the voltage was feeding through the switch to the sPOD "The Source". That activated the fan "turn off" relay, which then caused my engine to overheat. All I had to do was turn off the panel lights. A new switch fixed it. sPOD is forwarding the old switch to the manufacturer for analysis--they've never seen a failure like this before.

 

By the way, just an interesting historical note here: The first use of disabling the fan that I've ever come across was the very first overlanding trip by anyone. Some Oxford and Cambridge University students drove 18,000 miles from England to Singapore in the 1950s. During their trip they filmed much of it, and that journey is now available on DVD. It is there where they mention how they learned to "remove the fan belt" to prevent the underhood parts from being splashed by water, thus disabling them until they could dry everything back out.

Here's a pretty lengthy trailer for the expedition ...
http://www.youtube.com/watch?v=ns7MIJLmov4 And here's where you can order the full length video. Do be aware that these guys were college students and none of them was a professional photographer. I think that's part of the charm of the video ...

'First Overland' Home Page

 

I didn't know the history of the tape or the tie to the F-4 Phantom, very interesting. Thanks for the link, it prompted me to order more tape!

 

how do you make the wave infront of your jeep so the water level is down infont of your jeep?

 

Yeah, some of the folks were driving a little too fast in the video of mine for my taste. No wake because the water will rise in front of the Jeep and you don't want that.

 

Exactly....what's the rush?

 

LOL: True. I was enjoying the motorboat sound of my Jeep as we crossed. The video had the crossings out of sequence because a friend's wife drove my Jeep while I was on the other side shooting the crossing. She first drove across, dropped me off, then crossed again to be in the video. Of course, being the guy with a snorkel, I got volunteered to go first.

 

Thanks Mark

I like the switch idea, had an electric fan on an 87 Toyota pickup and the off switch failed and part of the fan blade went into the radiator on a river crossing, not good.

A big thanks for the lead on F4 tape, used it a lot when I was in the USAF back in the late 70's at Little Rock AFB on the C-130 and since then on cars, trucks and Jeeps, so I just order a few rolls