[Rollbar]

Just want to pass this info along-The Ford Contour or Mercury Mystique dual fan is a perfect fit on the CJ radiator and fits between the engine and radiator without clearance issues. Fits much better than the Taurus fan, which doesn't cover the entire radiator and usually has clearance issues.

That 400CFM is meaningless if 3400CFM is enough, even at 100F. On top of that, the Contour fan fit better to CJ radiators. These numbers are relevant when the fan shroud seal perfectly on the radiator, a small gap, mismatch, and the fan loose a substantial amount of CFM that pull through the rad.. So, with the Contour fans you get full capacity, with the Taurus on CJ radiator you get less than 3800CFM, might be even less than 3400CFM.



I''m a big believer in variable speed controllers. A Delta Current Control FK-35 variable speed controller. The fans only run at the speed necessary to keep the coolant flowing back into the engine at the right temp, which most of the time is much less than full speed. On cooler days, the fan rarely runs when the Jeep is moving because airflow due to motion is enough to cool. Soft start and variable speed makes the fans very quiet. No current spikes.










Just use the temp switch to activate the relay and the high speed fan will come on...
--------------------------------------

Now, for MAXIMUM Trail Redundancy, and absolute control of the fans,
(and using the cheapest & most common parts I could find!)
This will give you adjust ability of the low threshold setting,
The High threshold setting,
The fans will shut off when the engine shuts off,
The fans can run AFTER then engine shuts off,
The 'OVERRIDE' won't kill your battery if you forget and leave it on,
And you have a kill switch for deep water fording...


--------------------------------------
For those guys that need a refresher on Relays,


Remember!
There is a 70 amp relay out there!
It's the starer relay for a Harley Davidson motorcycle if you need to order by application...

We use a lot of them on electric air compressors, They look like this,
(pay attention to the LOAD LUG SIZE! The small terminals the standard 1/4 Inch you are used to seeing!)
Ignore the air pressure switches, this picture is actually for the air system stuff, but the relays are the same...


Now, most of you will try and find relays at the local Discount Auto Part Stores....

And you will be handed junk from China, Korea, South Africa, etc.
It's REALLY HARD to find a quality relay in the discount places!
------------------------------------------

Hella, Seimens, Bosch, etc. are th top quality companies, and you can find them by the loads for CHEAP in the junk yards!

This is really a diamond in the rough,
I got this at the local "U Pull" place for $1 and you couldn't put this together yourself for under $50!


Not only came with it's own mounting bracket, but has expansion room for another relay when I find it!


WATER PROOF! 'Weather Pak' connectors,
Locking wiring harness so it can't vibrate off or be pulled off by water, hanging mud or anything else short of hooking up your tow strap to it!


Top quality Hella relays! All of this for a one dollar bill!

Don't forget to cut the wires far enough down the harness so you can use the GREAT connectors on these!
Also, these are the original fan relays from an '89 Cadillac.
The Resistors in the picture are 0.125 Ohm, 50 Watt each.

---------------------------------------------

The Flex-a-Lite fan controller part number FLE31165 has a slow start feature on it of 60% and it gradually gets up to 100%. Has a override off, and override on feature as well. The cheapest I have found on line is here: http://www.streetrod...m/Products/1042

---------------------------------------------

Another thought, has anybody thought of using 3 relays to run the twin fans in series/parallel to get two speeds out of them as seen in this diagram:
http://www.autozone.....00c152800a2817 ----> Click on "Cooling fans 2001.
see the cooling system diagrams. Notice that it shows the PCM controlling the speeds but the same could be accomplished with two temp sensors and over rides could be added with switches.

--------------------------------------------

Another fan schematic, hand drawing. The relays are just common relays, #2 has the 87a post.


-------------------------------------------

Here is a different route, one controller for both speed, reading from the heater hose with direct contact with the water.



This controller is an on/off controller and not a variable speed one, I don't like the e-fan working like a clutched fan, I would have stay with what I had.

The Controllercan be used with any kind of sensor (NTC, PTC, Pt100, TcJ, TcK, TcS) and can be calibrated. I chose the NTC thermistor option and used an external thermometer for calibrating it.

The set temp on and off is adjustable, I can set it to start at 210 and off at 202 or 209 for on and 200 off, or any other temp. range.
It's also replacing my additional temp gauge and it's that accurate that I can see when the thermostat is opening.

In case of a bad sensor the controller can be set to run the fan at high or low constantly.

There are two built in led indicating when either of the fan speed is on.

A buzzer can be added for overheating warning.

Now, with this controller the temp vary from 207F to 200, with the previous setup it was 220F-195.

The manufacturer is a well known in the refrigeration market. The controller can stand high levels of humidity and heat.

Thanks to jeep hammer and the other numerous jeepers for the write up some of the pics.

[nero004]

good valuable info, thanx for the heads up

[Trailblazer]

Good info. Looks like i'll be making a trip to the u-pick soon.

[92SquareEye]

do you guys run the dual electrics in addition to the mechanical fan...or in place of? thanks!

-dave

[JeepinIan]

Generally they are run in place of.

[Rollbar]

Ian's right, I also have a small one that fits in front of the rad & behind the grill, switch it on when U crawl

[WRider]

Thanks for sharing this info...
This would be a much better alternative to the Taurus Fan I'm using right now...

[Monster76]

nice thing to know since i am planning on running elctric fans

[soflmuddin]

i have a friend with the 4.2 on two different jeeps. a 78-cj7 and a 85. does this clear the 4.2 setup? i used a ' 05 honda accord for my 5 with the 304. only had to trim for the top radiator hose. but this will not clear the 4.2.

[StuckZilla]

Would this work on a TJ? What's a fair junkyard price for the part?

[Rollbar]

 stuckzilla, on Jan 7 2009, 10:52 AM, said:

Would this work on a TJ? What's a fair junkyard price for the part?

Need to take measurments of a CJ rad, I'm not up on the TJ model.

[Rollbar]

Electric fan post updated with tons in new info/part numbers.

[Rockncrawl]

After reading the article on the electric fan conversion I found myself in a salvage yard pulling a Ford Mystique radiator fan. It is a great fit. I am still considering my options on fan controll. I am considering the Flexalite VSC.
Just wanted to say thanks for the helpful information.

[CrackerJack]

I am considering installig an electric fan. Got a question though - Where do the temp probes go? Is there any drilling/tapping or anything required to install the probes? Thanks

[Rollbar]

The temp probe goes through the fins of the rad.

[CrackerJack]

Thanks. I wasn't sure if the probe had to be in contact with the coolant or not.

[smallJEEP]

$99.00 or less on ebay with lifetime warranty...

[Big Red One]

I found a set of fans from an 96 Contour but EACH fan has an extra plastic piece that plugs directly into the fan motor ( I think it's the resistors) each piece has 2 yellow squares on the side about the diameter of a Quarter and thickness of a Dime, coated in yellow plastic, With H10 and H13 stamped on them. Then the plug like in your pic.. plugs into the other end of the plastic piece. I can remove the plastic piece all together and plug it in so it looks like your pic. Should I use these "resistors" and if so how is it wired in your Ultimate Redundancy diagram ( I have two wires coming from each fan), with each fan appearing to have 2 resistors each...

[Rollbar]

Not sure what fan you have. Post some pics.

[CrackerJack]

My understanding is that when you are driving and the fan is not running the motor, the spinning fan blades turn the motor into a generator and if there is no path for the energy to go it can damage the motor windings and reduce the life of the fan. What they do is install "freewheeling" diodes to take the generated voltage to ground. Not sure if that is what you are seing or not.

[Big Red One]

 CrackerJack, on Sep 19 2010, 09:53 AM, said:

My understanding is that when you are driving and the fan is not running the motor, the spinning fan blades turn the motor into a generator and if there is no path for the energy to go it can damage the motor windings and reduce the life of the fan. What they do is install "freewheeling" diodes to take the generated voltage to ground. Not sure if that is what you are seing or not.

My fans/shroud look exactly like the one in the first pic (fans attached to the Radiator) but where that harness plugs into the fan motors I have a plastic piece about 2" long that plugs into the fan motor and my harness plugs into the other end of the plastic piece, There was no white resistors (like in above pics ) on the car I removed the fans/shroud from. Thats why I think my "plastic" pieces are a NEW VERSION of the "white" resistors as seen above attached to the shroud on the above pics. I think I'm going to remove my plastic pieces from the "loop" and just plug my harness directly into the fan motor and find some of those white resistors on a different car at the u-pick-it ...

[Krocker]

quit complicated to me... it seem to be a very difficult project with confusing diagram...

[Rollbar]

More information:
After market new fans will not have the wiring harness for the motors. If you are purchasing used, you definitely want to get as much of the OEM harness as you can.

There are after market suppliers for the pigtails, but they are pricey: http://www.rockauto....4&parttype=2556

On a side note, you can get the plastic housing from Ford, however the crimp on terminals are not available. It's a Delphi part.

Here's a pic (do a search there are a couple of Contour Fan threads):




Actually, with the Contour fans you will want the controller and two additional relays. They can pull up to 60A and that single controller relay is not rated to that. This is an example of a safe way to wire the fans. This would be both fans Hi speed only.



http://www.summitrac...parts/FLX-31165

http://www.summitrac...31163/?rtype=10


Thanks to Hackfabrication & Coiz for their contribution

[Gutsy]

Rollbar...you know I have the YJ and changed the front clip to CJ. I have the original motor 4.2 that was with the YJ and the radiator was a big PITA to put in, plus I have A/C (well when I'm done with that). Tight fit as is. Oh by the way...I just finished with rebuild of motor... need to post pics - now equivalent to 4.5 if you know what I mean hehe. So, would this be a consideration to change out on my jeep? Would it fit/work?

[Rollbar]

I don't see why not even w/a three core rad. Measure it.

Remember the stock fan comes off, and, oh, BTW, keep the stock fan

[Big Red One]

Gutsy

I installed a 9 blade (16" diameter) Merc Sable fan from a 93 3.8L and it works very well with the VS Controller from Flex-a-lite. I modified the Sable shroud and it fits TIGHT with the 3 Core Aluminum I have, it covers about 80% of the Rad core, But it will take some engineering, The fan motor to water pump pulley clearance is about 1", and the fan is about 1" from the Rad core... Do you HAVE the A/C already, I just took mine off and am looking to sell it...

[TurboGus]

Man, I'm really digging this thread. Having just purchased a Mystique fan,



$40 at the wrecking yard for the last one within 50 miles, I'm ust about ready to start wiring it up. I can wrap my head around the relays and switches but the resistors are a new thing for me as are capacitors for slow starting these fans. Any help, diagrams, photos or parts list would greatly be appreciated. Now that summer's upon us here even in Oregon, I'm motivated to get these things installed. The setup I'm using now incorporates a small 13" Flex a lite fan originally installed by the PO as a pusher fan. I turned it around to a puller position and added a new 3 row radiator, Flow Kooler water pump, new hoses (with springs in lower AND upper rad hoses) and Omix Ada fan shroud (trimmed to get around the lower rad hose and drain petcock. Normally this ststem gets me by



with occasional summer temperatures reaching 100*, 'Black Betty's reaching 210*. Now for more modern Jeeps I've been told this is normal but 'Betty's' a '78 Renegade with a 360 motor.


....and NO they're NOT partridges

Anyways thanks and a lift of the lynch lid for your responses
Gus

[TurboGus]

Only NOW do I get it! That resistor (R27) on the shroud provides the slow speed from what I've read so far in another forum and I don't imagine that's going to jolt the fan motors as I feared! So just a 70 amp relay ahead of the whole shooting match should do the trick then! ....unless I'm wrong again.

[TurboGus]

 Rollbar, on 18 September 2010 - 11:51 PM, said:

Not sure what fan you have. Post some pics.

I think these are what he's referring to. Hope they won't interfere with my install;

[TurboGus]

BTW this fan cleaned up really well using De-solv-it and some ArmorAll

Before;


and after;



...not that I'm building some trailer queen