My Grand Cherokee e-fan conversion..very little gun content

Well, my 1994 Grand Cherokee has hit 200000 miles and it's about time to do something about it's cooling system.
It overheated on the freeway some weeks back and I about killed it driving to an off ramp (with it bucking and rattling all the way). I'm sure I hurt it some, but once it cooled down, I was able to put some water in it and drive it home. The head gaskets seem to have held and I can't tell much difference in how it runs, maybe there's a lope at idle. We bought it used and have put some hard miles on it. It has some idiosyncrasies. On the test drive, before we bought, it wouldn't start. They pushed it into the shop and I watched from a distance as they fiddled with the battery and got it started. I guessed that one of the cables wasn't tight, but later found they had added a 16 ga. wire from the battery negative post to the chassis. Pull that wire off and it won't start to this day (I have swapped out that wire for something heavier). The other thing was the cooling system was always marginal, prone to hissing and bubbling when you shut it down. It's continued to do that over the years despite getting a new radiator and water pump. Still, I like the durn beast quite a bit.
As I didn't kill it, I decided to go full Monte on the the cooling system. Flush, new radiator, new thermostat, new water pump, and a new fan clutch. I was feeling pretty good when finished with that, but it still wasn't up to speed. I did read on some forums that folks had swapped in early 90's, Ford Taurus, two speed, electric fans with excellent results. There were also quite a few different ways to do this. Some used Volvo relays and BMW sensors, others used relays and switches, and there were those with solid state controllers. I decided to go whole hog using a controller.
Here's the fan in place:
https://s19.postimg.org/5au29hn0j/800s1.jpg
It's mounted upside down from what it would be in the Ford. I made some brackets to hang it and sheet metal covers to close up some open areas on the shroud.

I mounted the two relays needed for fan power to a bracket I made from a defunct lawn chair:
https://s19.postimg.org/y1vhdai83/800r1.jpg

Here's the sensor I used:
https://s19.postimg.org/g0ccfho77/800sender.jpg
It's mounted in a heater hose. The adapter I used did not have place to mount a ground for the sensor so I welded a small tab to it.

I lucked out finding a hole through the firewall for the controller wires, as this year still had holes to mount a clutch. There was a cover plate but that came off without issue.
https://s19.postimg.org/5esh3hhvn/800hole.jpg

Grounded:
https://s19.postimg.org/n643hxxab/800g2_copy.jpg

Fused power:
https://s19.postimg.org/42as1lkg3/800h1.jpg

Continued...

The pièce de résistance is a controller from Dakota Digital (via Summitt Racing). Pretty cool little unit; it turns the fan's high or low speeds on/off at temps you select, turns on a fan when the AC is on, and allows the fan to run for a time you determine after shutting down the vehicle.
https://s19.postimg.org/6xnv8gog3/800controller.jpg
P380 shown for a size compaison.

So far this setup and some water wetter is working well. No problems what so ever on paved roads and most sand/dirt/gravel roads. I did have to shut the AC off several times when off road or on slow speed, dirt roads in the mountains, but I can live with that (even if it was close to 110). I haven't tried the mountains post charging the AC..hopefully that will help some.


https://s19.postimg.org/7fj0obe0z/800w2.jpg
https://s19.postimg.org/fay5gvd1f/800w.jpg
https://s19.postimg.org/lv0xn7r2b/20...82556_copy.jpg
https://s19.postimg.org/gm5wpc8n7/DSC02228_cr.jpg
https://s19.postimg.org/o3f44jy6b/image.jpg

Regards,
Greg

You done McGyver proud buddy. Overheating vehicles has always been one of my biggest worries. Just paranoid about it.
Never had any major issues to cause this trauma, just always a concern for me.

I put an Accu Gauge in my van I believe at Wynn's recommendation, I sometimes think I was better off not knowing. Now as it climbs a few degrees I get to worrying.

I'm used to the old 180 degree thermostats and my mechanic told me the van has a 195 OEM so that gave me 15 degrees less to worry about.

On the road trip a couple weeks ago and last year too it climbed to 210 on a few climbs. He said nothing to worry about but I worried anyhow ya know.

Did you gain any more miles per gallon of gas consumption? Less weight for the engine to turn over minus the fan and belt. I had a Fiat Spider with an electric fan and on hot days it would still be running after turning the engine off.

Quote:

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Originally Posted by Bawanna

You done McGyver proud buddy. Overheating vehicles has always been one of my biggest worries. Just paranoid about it.
Never had any major issues to cause this trauma, just always a concern for me.

I put an Accu Gauge in my van I believe at Wynn's recommendation, I sometimes think I was better off not knowing. Now as it climbs a few degrees I get to worrying.

I'm used to the old 180 degree thermostats and my mechanic told me the van has a 195 OEM so that gave me 15 degrees less to worry about.

On the road trip a couple weeks ago and last year too it climbed to 210 on a few climbs. He said nothing to worry about but I worried anyhow ya know.

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Thanks! When under load or creeping around, 210 is about what all my older vehicles run during the summer here. Do you remember when folks would hang burlap water bags on the front of the car to help with cooling?

Quote:

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Originally Posted by Ikeo74

Did you gain any more miles per gallon of gas consumption? Less weight for the engine to turn over minus the fan and belt. I had a Fiat Spider with an electric fan and on hot days it would still be running after turning the engine off.

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I haven't done any driving yet that would compare to that which I have an idea what the mileage was before. Mostly, I've been testing the set up....hard off road, heavy foot, creeping through residential areas and back roads (long periods of under 25 mph), etc. Doing that, the last fill up was about 15mpg which isn't bad for it.

Regards,
Greg

Quote:

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Originally Posted by Ikeo74

Did you gain any more miles per gallon of gas consumption? Less weight for the engine to turn over minus the fan and belt. I had a Fiat Spider with an electric fan and on hot days it would still be running after turning the engine off.

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When you mentioned the Spider, it brought back memories of when I worked at a Fiat, Lancia, and Alfa Romeo dealership. Drove a lot of Spiders, some with the 3 2 barrel setup. Fast....................................

McGyver indeed............................................ ............I wouldn't even know what they use as far as thermostats these days in these new fangled cars.:)

I've run a Taurus fan in my '96 Grand Cherokee for about 8 years. Killed one, one of the speeds quit working so I went to the junkyard and picked up another one. I just run a toggle switch so I get low-off-high, it's worked fine for me. Mine is my 'wheeling rig, and it doesn't see many miles each year. Did drive it from Denver to Moab and back this June, temps went up over 210 just a couple of times on the long climbs but that's it.

You will like it.

Needless to say but you are da man! Love those desert pics as well. That area is just made for jeepin. Maybe someday I'll get mine out that way. :)

Nice work Greg. I have an electric fan on a little toy car. It has a manual fan switch as well as the sensor to activate it. The thing works well to cool things off when it comes on.