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Electric Fan Upgrade


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  • Electric Fan Upgrade


    Installing a Junkyard Ford Taurus 2-speed electric fan into a Jeep YJ/CJ

    By: Alex Przygoda

    Probably one of the biggest mods that many 4x4er's want to do at one point or another is to upgrade the factory cooling system. One of the options available to us is to replace the stock mechanical fan with an electric one. Very high-power electric fans are expensive, so many hot-rodders, rockcrawlers, and general off-roaders have turned to what is considered by many to be the .44 Magnum of the Electric Fan World. The Ford 8C607 2 speed fan. This fan is found in 90-95 Ford Taurus and Lincoln cars with the 3.8L V6 engine. It is also known as the Lincoln Mark VIII fan. It is identifiable by three wires coming from the fan itself.

    One of the nice things about this fan, is that the shroud almost perfectly covers the entire YJ (and should cover CJ's also) Radiator. There are some negative sides, one being that you have to trim the shroud to make it fit, and that it draws nearly 100amps on startup, settling to 33amp constant draw, making it a major charging system drain. You may wish to upgrade to a 165 Amp high output alternator. You can get one here for around $160.

    Some other writeups for your enjoyment with wiring diagrams:

    The first thing to do is to go to the junkyard and find the fan. Most pick-a-parts have a $2 cover charge just to look around. I got my fan for $29. total out of a Lincoln Continental. There was another in a Taurus Station Wagon, but it was melted somewhat from a fire.

    Next, You will need to get parts to complete the system. Below is a list of parts I suggest, but you can piece it together yourself depending on how you want it to work based on some of the links to other writeups for your enjoyment.

    1 3 position ON-OFF-ON switch - one position for automatic, one position for water crossings(OFF) and one position for manual override of the thermostatic switch $3.99

    1 Junkyard Ford Taurus 8C607 two speed fan $29.00

    1 Hayden Adjustable Thermostatic Control Switch part #3653 $21.99

    2 Ford Starter Solenoid Switches for a '72 Ford F-350.. Autozone Wells part #F496 $12.60

    1 Inline Fuse Holder if you do not have a power-block $1.99

    n/a 16' of 10gauge Primary wire to be used for powering the fan and connecting to the battery approx. $8.00

    n/a 20' of 14 gauge primary wire to be used for wiring the switch approx. $8.00

    2 Heavy Duty Inline slow-blow fuses rated @ 80amps ?????
    1-2 Freewheeling Diode #1N5408 $3.00

    4 5/16"x 1/2" grade 8 bolts for securing the waterpump pulley $0.76


    Here's the Wiring diagram.

    Most of this stuff can be acquired at Pep Boys. I had to go to Autozone to get the Solenoids because Pep Boys were out and Napa wanted WAAAAAAAAAAAY too much for them.

    First thing to do is to remove the old clutch fan. Remove the air-box and loosen the serpentine belt. You can wedge a screwdriver inbetween the bolts on the pulley and then use a 1/2" wrench on the other nuts. You may have to unbolt the shroud to get enough clearance to remove the fan.

    Remove the Shroud (5 bolts on sides of radiator and a flexible skirt).

    Remove the water pump pulley, then remove the studs going into the water pump input shaft flange. Save these incase the electric fan dies and you have to replace the mechanical fan.

    Reinstall the water pump pulley using the 5/16" x 1/2" grade 8 bolts you bought, then re-tighten the serpentine belt.

    Trim the Shroud on the fan approx 1/2-5/8" on all sides except for the one with the pre-drilled mounting holes. Slip the fan into location upside down for clearance on water pump to mark for mounting points. Use the lower hole on the passenger side of the radiator (that now correseponds with the upper drivers side hole on the fan when it's right-side up) with one of the old shroud bolts to mark for the brackets on the drivers side and the upper passenger side bolt. I used two L-brackets with the old shroud bolts to attach it on the drivers side, and just drilled a new hole on the passenger side for the upper shroud bolt.

    You will notice the shroud isn't perfectly level with the top of the radiator. I did this on purpose. Take the Thermostatic switch probe and mount it in the space provided underneath the upper radiator coolant return line.

    and then attach the bracket for the switch to the shroud using self tapping screws.

    Attach the Starter Switches on the passenger side fenderwell. You will only need to attach to the S side to activate the switch, the I side is not used.

    Wire the switches to act independently, with the low-speed switch activated by the A/C Clutch (if you have air conditioning or an OBA system. If not, you can wire the low-speed fan to come on when the engine does by wiring the switch to the ignition-hot cable of your choice)

    The high-speed switch, I wired so that the thermostatic switch could turn it on, or it could be turned on manually with an override in the cab via the 3 position switch. One position of the switch would be "Automatic" and just supply power to the Thermostatic Switch which in turn would activate the fan when the coolant sensor read the proper temperature. The Manual override bypasses the switch entirely. I have the power for the switches coming directly from the battery so potentially the fan can run after the engine is off to act in a cool-down capacity.

    Because the fan is an electric generator when it is still spinning and off, it can store a slight charge, which has to be bled off somehow to keep the fan from damaging itself. Using the radioshack diode suggested will allow the fan to discharge itself.

    In any case. this fan is a good choice (probably one of the best choices in my opinion) as far as junkyard fans go. It's big, has a CFM rating of at least 2,000 CFM and is relatively inexpensive. Click the picture below to see a video of the fan cycling.

    Look for a wiring diagram shortly, many of the other sites have good ones to work from.
    84' CJ8-Project Jeep
    86' CJ7; A/C; 258 I-6; T-176; D-44rear; D-300; 66,500 original miles.


  • #2
    Good info, bookmarked. Thanks.

    '78 CJ-7, 304, Scout Dana 44s w/ a Detroit in the rear, T-150 w/ Dana 20, 4" Skyjacker susp and 2" body lift, 33" MT/Rs, Warn XD8000i, and others.

    '97 XJ, 4.0L, Dana 30 w/ Truetrac, Chrysler 8.25 w


    • #3
      Yea good info I read about that fan in Fourwheeler mag.
      75 blazer + 81 CJ-7 + 90 Wrangler = Tonka Jeep Dave