[mkt2488]

I recently installed an electric fan on my 94 (actually i installed 2 but thats a different story). I used the Hayden 3651 fan controller with the screw-in style probe. When i got the fan, controller, and heavy duty relay installed I immediately noticed that the fan controller and relay would chatter away (click, click). it would turn the fan on and off at the right temperatures, but it would randomly click and then really start clicking once it was getting ready to turn on or off the fan. I disconnected the fan and heavy duty relay from the controller and measured voltage on the output of the controller (+ switched). Every time that the controller would chatter it would put out a voltage less than 12v. Something like 2.5 or 3.5 volts. after a week of this--the controller took a dump. I was pretty ticked off about this, but since I had already installed all the wires for that controller--I decided to buy the exact same one again. In my head, i figured it was just a defective unit or something, and the next one wouldn't do that--WRONG! So now i'm sitting here listening to it click click click away. Has anyone else ran into something like this or have any suggestions? I really like the electric fan and how it works so well. However, I hate listening to the chatter knowing that soon, it's not gonna work.

 

[Poorboyz]

I had the same controller installed on my Bronco with 2 14" Hayden fans. The whole setup was a complete fail and I did a TON on research on here as well as a bunch other forums. Let me save you some time, money and effort in searching. Get a 18" Mark VIII fan from a junkyard. They have 2 different kinds, a 2 speed which has a black connector and a single speed with a white connector. The single speed with the white connector has a higher rated motor (RPM) than the black connector one. Depending what fan controller you get, I would suggest a FAL or a DCC controller. I personally went with a FAL cause I could not wait for the DCC site to come back online to be able to order one and then wait another 2 months to receive it. I built my own fan shroud that covers the whole radiator and along with the FAL controller it is working like a dream. If you need any pics of my install or have any questions I'll be glad to answer them.

 

[broncoflorida]

I'm running a hayden with 2 fans also. No problems and it has been installed for over 3 to 4 years nows. Controller sits secured to the front of the battery.

I would check your grounds and ensure that nothing is loose. I secured my ground returns to the front radiator support structure.

 

[mkt2488]

@broncoflorida
do you have the model with the probe that threads in or sticks between the radiator fins? I have the one that threads in. The first thing that i checked was my grounds. Actually, i went through and re-did all my connections just to be sure. No Change.


@PoorBoyz
I wish i would've gotten your post sooner. I already ordered a "zirgo" fan controller. I had never heard of the DCC controllers, but those look great. I did upgraded to the 18" fan yesterday (2 speed).

 

[tonyroc14]

whats the Mark VIII fan. Is that from a Lincoln? I was at the Junk Yard last week, and a few crown vics had large electric fans. My buddy took the fans from a Taurus for his truck. I am thinking about installing an electric fan myself, just wondering what fan would be best.

 

[broncoflorida]

@broncoflorida
do you have the model with the probe that threads in or sticks between the radiator fins? I have the one that threads in. The first thing that i checked was my grounds. Actually, i went through and re-did all my connections just to be sure. No Change.


.

I didn't use the stick thru fin probe, but I found a thread temp-sensor from a car ( suzuki iirc ) and since my t-stat housing was tread, I used that instead. Just test various sensors and adjust the temp-control to suite your needs.

I will post pictures and update this thread later.

 

[Poorboyz]

whats the Mark VIII fan. Is that from a Lincoln? I was at the Junk Yard last week, and a few crown vics had large electric fans. My buddy took the fans from a Taurus for his truck. I am thinking about installing an electric fan myself, just wondering what fan would be best.

Mark VIII fans are from the Lincolns. Taurus are similar, but they are 16", not 18" like the Lincoln and the motor on the Taurus fans don't have as high RPM as the Lincolns. If you have the space go with 18" lincoln fan. They use those fans on race car application and they can easily cool 1000+ horsepower cars. I've done a ton of research and I can tell you from now on if I ever have a cooling problem I will be sticking a 18" Lincoln fan coupled with either a FAL or a DCC controller.

 

[SnowTom]

Mark VIII fans are from the Lincolns. Taurus are similar, but they are 16", not 18" like the Lincoln and the motor on the Taurus fans don't have as high RPM as the Lincolns. If you have the space go with 18" lincoln fan. They use those fans on race car application and they can easily cool 1000+ horsepower cars. I've done a ton of research and I can tell you from now on if I ever have a cooling problem I will be sticking a 18" Lincoln fan coupled with either a FAL or a DCC controller.

How do the 2 speed controllers work? When do they kick on/off, and what affect does turning on the air conditioning have?

 

[JScatt]

whats the Mark VIII fan. Is that from a Lincoln? I was at the Junk Yard last week, and a few crown vics had large electric fans. My buddy took the fans from a Taurus for his truck. I am thinking about installing an electric fan myself, just wondering what fan would be best.

The V-8 T-bird also uses the big fan, its two speeds and moves a ton of air. Might even be the same as the lincoln, plus there is always more t-birds at the J/Y.

As far as controllers go, you can also get one that goes into a water jacket, t-stat housing or where ever you want to put it. Made by Painless Wiring and available at Summit Racing.

 

[broncoflorida]

Here you go

If you can find a a threaded t-housing, this might be the solution that you need. A stang buddy of mine has something that is thread into the block top drain plug. You basically remove one of the plugs close to the controller location and thread in the sensor plugs. Does the same thing as mine.

I ran my wire on top of the upper hose back to the controller , which is located at the battery.

I believe your problems are due to a bad ground or power.

On the sensors, keep in mind that the temp change of the coolant changes the resistance with these sensors. So you can try various threaded sensor if you don't have an adjustable controller and you can test them with a simple VDOM and pot of boiling water and thermo-meter.

:thumbup

 

[Poorboyz]

The V-8 T-bird also uses the big fan, its two speeds and moves a ton of air. Might even be the same as the lincoln, plus there is always more t-birds at the J/Y.

The size, fan and shroud are the same as the Lincoln, the motor RPM is not. Lincolns have the fastest RPM out of all of them. Here is some info I gathered from another forum:

"I know for a fact that there are three part numbers for the Mark VIII fans as follows:
93-96 F3LY 8C607 A 1100 on low and 1850 on high RF123 Y=lincoln/mercuy
97's F7LZ 8C607 AB 1800 on low and 2225 on high RF56 Z=ford
98's F8LZ 8C607 AA 1800 on low and 2225 on high RF64 Z=ford

All these fans are single speed PWM controlled by the car. I believe the middle wires on ALL of these are either tied together at the motor; or don’t exist (It has been reported that 97 and 98 have only two wires in their pigtail).

There are several stock pigtails that have been reported as taken from Mark VIIIs:
2 black 1 green (all same gauge, blacks tied together at motor)
2 black 1 blue (all same gauge, blacks tied together at motor)
1 black 1 brown or orange 1 Blue (different gauges for the positives)
1 black 1 Org/Blk - Low 1 Blue - High (different gauges for the positives)
1 Black 1 BRN/Org - Low 1 Brn/Yellow - High (different gauges for the positives)


I don't believe that Ford was putting different harnesses in the engine bays within a model year and I doubt it changed between 93-96 particularly the ones that have differnt gauge wires. If this were true I have yet to see a wiring diagram that proves it.

Fan/Replacement_Motor/Vehicle Data:

RF123 75717 Mark VIII 93-96 (1-speed 18" ?)

RF24 75715 T-bird LX 94-97 (2-speed 18" ?)
Cougar XR-7 94-97
(maybe others)

RF125 other Taurus GL 90-95 (2-speed 16" ?)
Taurus L 91-92
Taurus LX 90-95
Taurus SE 95
Continental 90
Continental Executive 91-94
Continental Signature 90-94
Sable 90-95
(maybe others)

I think the confusion lies with the RF24, It has the unique Mark VIII fan blades and shroud but a different motor. This is a true 2 speed motor; presumably these cars don’t have PWM controllers and just use two speeds whereas Mark VIII can achieve multiple speeds by PWM. I think this fan is mistakenly referred to as a MarkVIII fan. This helps explains all the different wire colors and sizes that are reported as being a Mark VIII pigtail. The shroud and fan blades looks identical but the middle terminal on the RF24 motor is not a "dummy". The plastic plug at the motor is black instead of white and it does not have the “inspection cover” near the plug. I suspect RF24s were assembled in Canada and RF123s were assembled in Mexico which accounts for that misconception. Presumably, high speed on the RF24 motor is not as good as the M8 motor wired straight to battery but I have read threads that say high on a 2speed is better than the single.

*** UPDATE *** I pulled the fan blades off my 93 1-speed and the motor is #F3LU - 8K621 - AA and is stamped CANADA. It crosses to a #75717, so that blows up this 2 speeds come from Canada story. I have also learned that the two-speed motor is #F4SH-8K621-AA which crosses to a 75715 *** UPDATE ***

I have read threads where the author swears that he pulled the fan himself from a 93-96 Mark VIII and it was a black plug 2speed. IF this is true and that is a big IF; I suspect that Ford, in a pinch, would sustitute an RF24 if they were out of stock on RF123s for the 93-96 model. Theoretically the VCRM wouldn't care which was there since both fans have 2 wires that are positive and one ground. I bet due to the way the VCRM pulses based on conditions (engine temp, A/C, etc); the net cooling effect is the same whether both positives are one speed or two. The reverse however is not true. You can't put an RF123 in a T-bird/Cougar, although the fan blade and shroud are the same. Their relay system expects 2 different speeds depending on wich lead is energized. You would be on high all the time which is not desirable due to the current draw and startup spike.

As for the notorious "Taurus fans"; the RF24 and RF125 are both 2 speed motors but one drives an 18” fan (RF24) and the other drives a 16” fan with a curved blade and differnt shroud (RF125). Neither on high is as powerful or pulls more air than any of the three Mark VIII fans (RF123, RF56, RF64). On a side note, it appears that regardless of whether you have a 1 or 2 speed; any fan having 12v on both positive wires at the same time is not good. It makes high speed slower on a 2-speed and can affect the life of the one speed."

 

[nevadagary]

I used the big e-fan out of an 06 Crown Vic taxi cab...same as a police cruiser. It is a two speed but I have it wired for single speed and it is awesome. It will suck the skin off an apple.....HAHAHAHAHA. I also use a through the fins probe but I installed it right in the upper radiator hose where it comes into the radiator so it is right in the coolant flow. I did an installation thread here for it but don't have the link handy. I installed the fan inside the stock Bronco shroud. It works amazingly well and I have said it before and I will say it again here this has been the BEST modification I have made so far on my 96 Bronco.

 

[CrazyBRONCOguy]

I would look at the grounds as mentioned also how is the controller hooked up to the battery? I am running the same conrtoller in mine without issues. Though when I ran mine I did not wire the fans to this controller, instead I used it to turn on another set of relays with direct battery power for the fans. Almost sounds like its getting overloaded, or there is a loose connector somewhere.... I have had the cheap fuse holder these come with have issues before, might be another place to look.

 

[cjwchoppers]

crazybroncoguy. would you be ablem to post a wiring schematic of your set up

 

[CrazyBRONCOguy]

I can but i have to make it, no big deal. Basically you just use the fan positive from the hayden unit and connect that to the switched side of the relay for the fan.

 

[mkt2488]

I appreciate all your help. checking the grounds was the first thing i tried when i started getting the relay chatter. I actually even redid them just to make sure, but the grounds were very good. The only way i could have made them better would be to run a shorter ground by locating the controller closer to the battery. The hayden controller power was hooked up to the incoming 12V into my under-hood fuse box. Like I said earlier though, I've bought two of these now with them both failing in the same manner. So, I cut my losses and picked up a Zirgo fan controller. I haven't hooked it up yet, however I really like the simple design of the controller itself. Also, it appears that the zirgo controller switches the common/ground to the heavy-duty solenoid/relay. I like this idea, since i've heard that (theoretically) when switching the common as opposed to hot, you'll get less arcing thus a better long-lasting contact. I'll hook it up this weekend and see if i have any better luck. maybe I'll post a pic or two.

 

[Poorboyz]

Never heard of Zirgo, I'll have to check them out. The reason I decided for either the DCC or the FAL was because they were both rated for the 35+ amps my fan pulls and they both have a soft start so it doesn't put a huge load on the system when starting the fans.

 

[mkt2488]

here's how i had the hayden controller hooked up. i used 10 gauge wire from the solenoid to the fan, and to the battery from the solenoid. I think it was #4 wire that I'm using for the ground from the driver side fender (where the controller was mounted), back to the battery.

 

[mkt2488]

Never heard of Zirgo, I'll have to check them out. The reason I decided for either the DCC or the FAL was because they were both rated for the 35+ amps my fan pulls and they both have a soft start so it doesn't put a huge load on the system when starting the fans.

Yeah, I wish i would've heard of DCC or Flex-A-Lite before I had ordered the zirgo. Oh well, I think i got it for like $40. If it ends up being quality, maybe it'll be another option for other users. Those DCC ones sound real nice, but it seems they are pretty hard to get ahold of. I'll let you all know how it turns out.

 

[Poorboyz]

Can you post a few images of it? What is the amp rating on it and what features does it have? DCC and FAL both have different type controllers, the one I got was $110 shipped.