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

[gb6491]

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 (https://postimages.org/)
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 (https://postimages.org/)

Here's the sensor I used:
https://s19.postimg.org/g0ccfho77/800sender.jpg (https://postimages.org/)
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 (https://postimages.org/)

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

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

Continued...

[gb6491]

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 (https://postimages.org/)
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://postimg.org/image/60hfzlcxr/)
https://s19.postimg.org/fay5gvd1f/800w.jpg (https://postimages.org/)
https://s19.postimg.org/lv0xn7r2b/20160210_182556_copy.jpg (https://postimages.org/)
https://s19.postimg.org/gm5wpc8n7/DSC02228_cr.jpg (https://postimages.org/)
https://s19.postimg.org/o3f44jy6b/image.jpg (https://postimages.org/)

Regards,
Greg

[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.

[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.

[gb6491]

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.
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?

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.
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

[berettabone]

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.
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....................................

[berettabone]

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

[Ken L]

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.

[GROTMAN]

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. :)

[Alfonse]

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.

[gb6491]

McGyver indeed............................................ ............I wouldn't even know what they use as far as thermostats these days in these new fangled cars.:)
Yep, thank the powers to be for the internet:angel:


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. :)
Thanks! Hope to see you (and all others) out this way:)

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.


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.
You two have me feeling good about the decision to go with the electric fan...especially since Ken L uses the same fan in his ZJ. Thanks!!

On a side note: as I was in the groove, I decided to work on a few other small issues the Jeep has.
The driver's side master panel had the only controls that would work the power windows and power door locks. I found two broken wires in the bundle between the driver's door and the frame that fixed all that once the breaks were repaired. I also replaced a faulty rear door actuator while I was on the doors.
My cruise control was intermittent to mostly dead. Replacing the brake light switch solved that.
The only real thing left to do is drop the gas tank as I'm pretty sure the fuel level sending unit is shot.

Regards,
Greg

[AJBert]

Might fine looking install, looks like the factory put it all together. Color me impressed! I've been toying with the idea of putting electric fans in my Blazer for a few years but me and electriconical gizmos don't mix terribly well. I can do basic but not much more than that. I don't have a problem with cooling in the Blazer but it would be nice to free up some extra HP.

I'll be picking up a project tomorrow, a 1972 GMC 3/4 ton 4x4 and will more than likely put electric fans on that. Plan for it is as a hunting/camping/fishing rig and not an offroad toy. I have the Blazer that will turn into more of a toy as it has been handling the towing of our little travel trailer for the aforementioned activities. The Blazer does fine with the towing until I cross passes above 10,000 feet. It makes no problem but I've been passed by little old ladies walking up the pass with their strollers and really want something that can handle more weight that has a bed and more power.

[gb6491]

Might fine looking install, looks like the factory put it all together. Color me impressed! I've been toying with the idea of putting electric fans in my Blazer for a few years but me and electriconical gizmos don't mix terribly well. I can do basic but not much more than that. I don't have a problem with cooling in the Blazer but it would be nice to free up some extra HP.

I'll be picking up a project tomorrow, a 1972 GMC 3/4 ton 4x4 and will more than likely put electric fans on that. Plan for it is as a hunting/camping/fishing rig and not an offroad toy. I have the Blazer that will turn into more of a toy as it has been handling the towing of our little travel trailer for the aforementioned activities. The Blazer does fine with the towing until I cross passes above 10,000 feet. It makes no problem but I've been passed by little old ladies walking up the pass with their strollers and really want something that can handle more weight that has a bed and more power.
Hey, thanks! :)
The electrical is mostly running and connecting wires.
I think I spent the most time (in proportion to what needed to be done) looking for a way to get the wires for the controller through the firewall.
There are quite a few tutorials on line that list what you will need.
One of the reasons I went with the Dakota Digital stuff was that I could get the controller, a matched temp sender, and appropriate relays from the same place with free shipping. Dakota Digital also has a good wiring diagram in the controller manual: http://www.dakotadigital.com/pdf/PAC-2750d.pdf

The 3/4 ton sounds like a fun project:cool:

Regards,
Greg

[Ed M]

Greg - You're just a talented individual.

I'd love to see you, Alfonse, and Harrylee get together and brainstorm in your workshop sometime.

It'd make the Manhattan Project look like a daycare center....

[jeepster09]

Greg - You're just a talented individual.

I'd love to see you, Alfonse, and Harrylee get together and brainstorm in your workshop sometime.

It'd make the Manhattan Project look like a daycare center....

That could be very scary .... to much talent unleashed at once! :ohmy:

[yqtszhj]

I love those figure out a way besides how it was made fixes. Too cool.

[Bills1873]

Good install and superb pics, as usual! Installed electric fans on my 2002 6.0l chevy truck a year ago. Mega good results! A/C works better, transmission cooler when towing, worth every penny and install time! The beast will thank you Greg!

[kenemoore]

Electric fan for your driving habits makes a lot of sense, max cooling regardless of engine rpms.

[ct9kahrtoter]

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.Me too, the same way, but I got seriously stranded in a blizzard once....years ago.

[gb6491]

Greg - You're just a talented individual.

I'd love to see you, Alfonse, and Harrylee get together and brainstorm in your workshop sometime.

It'd make the Manhattan Project look like a daycare center....

That could be very scary .... to much talent unleashed at once! :ohmy:
Thank you, but shoot, I'm a technician..a dabbler. Those boys (and some others here) are the brains....getting them together might be scary, but it sure would be interesting to see what they come up with.

I love those figure out a way besides how it was made fixes. Too cool.
Me too; in my case, I think it's the hill billy blood. Thanks!


Good install and superb pics, as usual! Installed electric fans on my 2002 6.0l chevy truck a year ago. Mega good results! A/C works better, transmission cooler when towing, worth every penny and install time! The beast will thank you Greg!
Thanks and I appreciate knowing that your install is working out for you....the more assurance the better.
:)


Electric fan for your driving habits makes a lot of sense, max cooling regardless of engine rpms.
I do believe you are correct boss:yo:

Regards,
Greg

[Armybrat]

Interesting improvement you did there. You're probably good to go for another 200,000.

My 2000 Cherokee Sport (bought it new in October 1999) has only had the usual maintenance so far, plus a recent brake job. It is perfect for driving around town, as it is pretty compact (7" shorter than the little Saturn SL sedans) and has a tight turning circle. It has almost 95,000 on the clock.

Did have to replace the headliner a couple of years ago. Only drawback is the 2WD. Wish it had the 4WD, but it can still climb in & out of the creek ford (18" of water) with no sweat.
Wife doesn't want to go on long road trips in it any more, as the short wheelbase ride is uncomfortable for her back nowadays. Used to drive it down to South Padre Island with no complaints.

[gb6491]

Interesting improvement you did there. You're probably good to go for another 200,000.

My 2000 Cherokee Sport (bought it new in October 1999) has only had the usual maintenance so far, plus a recent brake job. It is perfect for driving around town, as it is pretty compact (7" shorter than the little Saturn SL sedans) and has a tight turning circle. It has almost 95,000 on the clock.

Did have to replace the headliner a couple of years ago. Only drawback is the 2WD. Wish it had the 4WD, but it can still climb in & out of the creek ford (18" of water) with no sweat.
Wife doesn't want to go on long road trips in it any more, as the short wheelbase ride is uncomfortable for her back nowadays. Used to drive it down to South Padre Island with no complaints.
I wouldn't mind that:)
I like the Cherokee. I went on a lot of hunting trips with a buddy who had one 1988-1993 time frame. It was a four banger, but always got us where we wanted to go. We have a 1994 Country, but it's setup for mostly off pavement. It usually stays in 2wd with 4x4 being mostly used for deep, loose sand.
They are pretty rugged, I read about a police department finally retiring their Cherokees with 300000 on them: http://www.allpar.com/squads/police-cars/cherokee.html
Regards,
Greg

[AIRret]

I'm WAY too impressed.
The last time I worked on my cars they didn't have electronic ignitions!!! AND, all I did was change the oil, oil filter, antifreeze, and rotate the tires.
I'm a neophyte!

[gb6491]

I'm WAY too impressed.
The last time I worked on my cars they didn't have electronic ignitions!!! AND, all I did was change the oil, oil filter, antifreeze, and rotate the tires.
I'm a neophyte!
Thanks MB! There's no need for you to work on cars....penal labor can take care of that;)
Regards,
Greg

[berettabone]

A friend of mine had a 1975 Cherokee. 360 V8........Quadra-Trac 4x4. He beat the heck out of it for years, and the only real issues were with the drive train. It did always run hot though. We used to call it the Rat Patrol vehicle. One night, we used it to chase down a rat, the biggest rat I've ever seen. Rivaled some people's dogs. We were down by the old brewery, where all the grain was stored. Want to find large rats? Go to the grain. I jumped in the drivers seat, because I wanted nothing to do with a giant rat. My buddy hopped out, I cornered the rat with the Cherokee, and the rat proceeded to jump at him repeatedly. Crazyness. I'm yelling at him to watch out, as he's trying to get it, but yet had to watch out for the giant leaping rat. He finally got a kick in, which must have been a good one, because it slowed the rat down and caused it's eventual demise. If you haven't figured it out yet, there was an awful lot of alcohol consumed that evening. Oh yes, I have many Cherokee memories..................:)

[gb6491]

LOL, love that story :D

[b4uqzme]

Years ago a buddy had a Comanche pickup with overheating problems. He asked me to come take a look. What I found was red gunk oozing all around the t-stat housing. Buddy told me he used a sealer instead of a gasket (probably because he crimped the gasket that came with the new t-stat). He showed me a can of stuff with a label reading: "seals everything". Well it obviously doesn't seal everything. We fixed it right. i made him replace some worn out hoses and clamps while we were at it. It ran for years after that. We hauled mountain bikes all over the place. I gave him an old aluminum cap and we used it for camping. Good truck that one. Not a bad buddy either.

Great work there Greg.

[gb6491]

Years ago a buddy had a Comanche pickup with overheating problems. He asked me to come take a look. What I found was red gunk oozing all around the t-stat housing. Buddy told me he used a sealer instead of a gasket (probably because he crimped the gasket that came with the new t-stat). He showed me a can of stuff with a label reading: "seals everything". Well it obviously doesn't seal everything. We fixed it right. i made him replace some worn out hoses and clamps while we were at it. It ran for years after that. We hauled mountain bikes all over the place. I gave him an old aluminum cap and we used it for camping. Good truck that one. Not a bad buddy either.

Great work there Greg.
Thanks and thank you for another excellent Jeep story:)

I wish they had never dropped the Comanche. I've seen where Fiat said there will be a Jeep pick up, but I've also seen where it has been pushed back to 2019:
http://www.roadandtrack.com/new-cars/future-cars/news/a29009/2017-jeep-wrangler-pickup-info/

Regards,
Greg

[gb6491]

A small update:
I really like how the e-fan cools, but I had some trouble with the fan's high speed wiring. The fuse holder I used for the high side (30 amps) started to melt. Part of the issue seems to be the quality/type of holder I'm using. I think it has enough resistance to create hot spots where the fuse legs install (one leg of the fuse showed some heat damage). I also think the holders might have been mounted to close to the engine and headers.
https://s19.postimg.org/42as1lkg3/800h1.jpg
Melted holder:
https://s19.postimg.org/6w3i01uir/image.jpg (https://postimg.org/image/muc7q6oqn/)
As a fix, I've moved the fuse holders away from the engine and tightened the fuse connections by squeezing the connectors in the holders nearly closed before inserting the fuses. Two of the holders (controller power and fan low) were good before, but I moved them behind the engine bay fuse box. I moved the fan high fuse holder to a spot where it is shielded by the battery. I made a simple bracket to secure it to a cold air conditioner line hoping that might help some with the heat (it was also a convenient place to mount it). So far, so good...the holder gets hot, but doesn't show any signs of melting
https://s19.postimg.org/5ibv4qv9f/fh2.jpg (https://postimages.org/)
https://s19.postimg.org/dp3uwblc3/fh3.jpg (https://postimages.org/)
https://s19.postimg.org/j1spag98j/fh4.jpg (https://postimages.org/)
If this doesn't work long term, my back up plan is to try this:
https://s19.postimg.org/qj1wpnyrn/fh5.jpg (https://postimages.org/)
Regards,
Greg

[yqtszhj]

I like that backup plan. How much would you say the AZ heat contributes to the higher temps causing melting under the hood.

I had this electronics instructor one time that was retired from the air force and he said that some of the materials made to deal with the heat and pressures of automobiles were comparable to military grade stuff. When I started having to do research for components for computers I found out how cooling dependant most things are.

[gb6491]

I like that backup plan. How much would you say the AZ heat contributes to the higher temps causing melting under the hood.

I had this electronics instructor one time that was retired from the air force and he said that some of the materials made to deal with the heat and pressures of automobiles were comparable to military grade stuff. When I started having to do research for components for computers I found out how cooling dependant most things are.
I'd guess the higher temps just edge stuff closer to their failure point. On really hot days, the cooling fan flow feels much like a heat gun.

In my application, the controller will turn the fan on anytime the AC clutch kicks in. Every time I've checked that, it seems the fan is in high mode. These are "hard" starts when compared to engine cooling where the fan starts in low and switches to high at a certain temperature; that gives the high side a running/soft start as the fan is already turning. I think the current spikes from the hard starts might be the major factor in the fuse holder heat. I could disable the AC clutch input on the controller, but I do like how quickly it makes the AC blow cold before getting up to speed or before the engines warms up enough to kick the fan on.

Regards,
Greg