Mechanical Fan to Electrical Fan

[MPGmustang]

I know this has been done quite a number to times, but I am making a good guide for me (and for others to read up on in the future) as I replace my Mechanical fan to an Electrical fan.

the reason I want to convert to mechanical fan is here in AZ I travel through traffic all the time in the city, and at idle the mechanical fan won't pull enough air to cool the engine down and my AC. usually I just shut off the AC and swim in the 110+ heat. well I'd rather not.

First I plan on upgrading my 60amp alt to a nice healthy 100-130amp alt, and get rid of the anameter and external regulator
Anyone have a plug and play setup? link will help (electrical blond here)

Next I'll need a Fan, or fans... I'm thinking I would like 2 electrical fans, reason behind is I won't need the 2nd one during winter, and I can save load on the electrical system, and last fitment of the 2 fans let me get deaper fans. My radiator surface is 17Tallx16Wide and I have roughly 2.5 inches distance to my water pump pully. My restrictor is 2.5 inches, I have to find a fan that can fit between my water pump pully and my radiator without touching the pully. BUT If I offset my 2 fans I can safely go 3.5 inches with more room to spare at most areas that I think the motor will be.
I'm thinking of 2 of these fans. 9inch Electric Fan @ 1550 CFM

control module I would Like to step up the fan's speed as needed, not a "on/off" but low-med-high kinda operation. both will run the same time initially
I found this "Flex-a-Lite" kit that sounds like it should do the trick (or even just a med/high is fine)

for these two mods to the electrical system I should be able to aleviate much of the load under the just from the alt upgrade, and the fan will give mpg and HP increase. and the steping module will help negate spikes in the electrical load.

I need help finding or seeing things I don't know about. Thanks guy's this is awesome :mrgreen:

 

[69.5Mav]

"Flex-a-Lite"

Wow thats $154.00.

I would use two Temperature switches. The ones from an 82 sentra are cheap. I'd put one each in the upper and lower Raidiator hoses. Then each would turn on it's own fan through a relay. That would alow the increasing load on the cooling system to turn on each fan as additional cooling is needed.

For the air conditioner I'd turn on both fans using diode isolation. This should be a whole lot cheaper.

 

[MPGmustang]

"Flex-a-Lite"

Wow thats $154.00

yeah, I just wanted something like that, I like the "low med high" fan speed factor, it should negate "current spikes"
after thinking a bit more about it I think I just want a "car on = fan on @ 195 off @ 175/2nd fan on with AC" setup. that way, IF one fan can cool the car and A/C I will have the normal fan turing on/off when not needed.
Maybe one of these will work better.
Derale or Hayden

And I have found my ALT upgrade, on ebay there are 100amp 3 wire chrome alt's for $70 shipped with a new regulator, I think that is my best option
How would I correctly disable my "alt dummy" light? I'm going volt guage and don't want 100amps inside the car. :nono:

69.5Mav - I was looking for cheap $20 adjustable ones, they'd come out to the same price and don't have the AC tie in, and honestly you lost me with "diode isolation" :

 

[JackFish]

I've got some parts together to do this.
I'm going to use a dual fan from a Contour/Mystique, as it fits the fox-body rad and is very thin.
I got a couple of adjustable temp switches off ebay.
They look a lot like hot-water tank thermostats.

I upgraded to a 3G alternator last fall.

 

[64 200 ranchero]

i got my universal fan from kregan for 40 bux and ran it with a relay with a fuse through my acc power on the stock fuse block for the relay coil and from the batt to the fan, i spent less than 60 bux

 

[MPGmustang]

should I invest in a fan shroud for these electric fans? there's not much room that it would help "direct" the air thorugh the fan but thought I might consider it

 

[69.5Mav]

honestly you lost me with "diode isolation

Well, You take the line from the air conditioner that turns on the fan and run it to the Anodes of two diodes.
Then you take each diode cathode and run one to your low temp fan (the one with a thermostic switch in the upper radiator hose) and the other cathode to your High temp fan (the one with a thermostic switch in the lower radiator hose).
That way when the air conditioning comes on both fans will come on but when off will alow only one fan to come on.

The way this set up works is that when the coolent temp rises to the turn on point of the switch in the upper radiator hose the first fan will turn on and if it provide enough cooling the second fan will remain off because both switches turn on at the same temp and the one in the lower radiator sees coolant that is cooler then the upper Radiator Hose. But if the first fan does not provide enough cooling then the coolant temp will rise until the lower switch reaches its turn on point at which point both fans will be on. Hopefully no further cooling will be necasary cause thats the limit, the most that can happen is the coolant temp will continue to rise increasing the delta temp and shedding more heat until coolant boil over is reached at which point you should stop.

 

[MustangSix]

How about some sort of switch that prevents the fans from coming on when the car is moving. The fans probably wouldn't come on due to temps, but the AC could cycle the fans and that might not be necessary. In newer cars the ECU handles that function by looking at the vehicle speed sensor (VSS).

Maybe a micro switch triggered by an air vane/ flap? At some speed the flap would trip the switch and the fans would not come on.

 

[MPGmustang]

WEEEEE!!!! VROOM!!! WEEEE!!!

WWhoa!!! I can't believe what engine I got in there 8)

the sound is SO much nicer too... I think I'm converted...

that's the good news, the bad news is...

The too fans cna't keep up, I got 2 9inch fans that can't handle red lights, at night, when it's 85* outside... I tried the AC and well it got too hot too fast, exept when moving, it was able to maintain a steady temp, granted I don't know the temp, but the needle was more steady while the car was moving, Maybe there are more powerfull 9inch fans... I do have about 1.5 inch room to grow... away from radiator, so maybe a shroud... it'll have to be custom... think there's some alum staming place nearby...

anyways, it's late, i'm going to go dream about my car on the dyno next week reaching 120hp (think that's possible, wait don't tell me, it's a good dream)

 

[69.5Mav]

Are you running ported or manifold Vacumn advance? If ported try switching to manifold.

What is you idle air/fuel ratio? It might be too lean. Try richenning it up 1/4 to 1/2 turn on the idle mixture screw.

Let us know what you find.

 

[MPGmustang]

Are you running ported or manifold Vacumn advance? If ported try switching to manifold.

Yup, I'ming running manifold vac


I will try fiddling with the idle screw...


so i took my temp gun around the engine head, and CYL's 4,5,6 all reach +230* before the 195* t-stat opens, I don't think this is healthy, any suggestions?

now that I have electric fans, should I pull that t-stat? or put in a 175* and control the engine temp via the fans?

 

[MPGmustang]

numbers are in from this conversion, so far I only have "highway" numbers, I'll be working on city numbers for the following weeks...

phx to kingman - 24.33mpg
kingman to st george - 21.67mpg (did have the AC on part way, only at higher speeds 65+)
st george to provo - 22.24mpg
Round around all weekend in SLC - 18.3mpg (alot of this was warming up and getting the car to defrost)
ogden to panguitch - 23.88mpg (I spilt the gas as I filled it up)
Panguitch to flagstaff - 24.92mpg (I spilt as the pump didn't auto shut off)
flagstaff to Chandler - 28.99mpg (I didn't believe it either, so I pumped it again and spilt with only .01g pumped in :roll: )

granted flag to chandler is all down hill, my last record shows 24.4mpg on that very road with my mech fan. so I think the fans will pay for themselves...

arty: arty: 28.99mpg arty: arty:

I feel great now

Now, the fans work great, without AC, this is a problem. they are each really only 441cfm, I have looked them up on the manufacture website, waste if money... and so I WANT AC... I measured the area between rad and pulley, I have 2 3/8 inches, I have found a 2 5/8 inch fan that can move 2100cfm on high and 1700cfm on low... I think I'm going to hook up the low to the relay and the high to a switch that I can control, this way, if it's not cooling enough I can turn off the relay assembly and keep the fan on full blast, Its just a cheaper version of a dual speed fan controler... or for teh first little while, connect it up to the high speed on the relay...

the fitting issues I've figured out, I'll move the rad closer to the condenser by modify'n the rad support mount area, not the support but what the rad bolts too.

now A question on strucural integrity of the rad support. I notice that the rad is "recessed" towards the engine. can I SAFELY message it back 3/8 of an inch to have the fan fit with 3/16 of an inch to spare? or is that too close and I need more room between fan and pulley.

Thanks for your relies.
Richard

 

[MPGmustang]

oh and Mav, thanks for that tip, 1/2 turn on the idle mixture helped with temp, it doesn't spike as much anymore.

 

[bucfan1234]

Thanks for the thread on this. I am going to tackle this conversion next week.

 

[MPGmustang]

Bucfan1234- as you have a 67 you'll probably have more room than I have, take measurements and see what you can fit, I'd be intrested to hear how much room you have between the pulley and radiator

 

[bucfan1234]

I took the mechanical fan off this evening, should get the electric fan and controller in the mail on Thursday. There is 3-1/4" between the radiator and the bolt heads, 3-1/2" to the face of the pulley. I don't have AC, and my radiator is a repro 3 row.

 

[bucfan1234]

t was cool out today, mid sixties, so I put the new rear shocks on and took her for a drive with no fan. Here are some initial observations.

Wow, I had no idea how much racket that fan made. It was really, really loud at idle. In fact, for a time I thought my water pump was on its last leg. Now the motor is much, much quieter at idle, and without the distracting fan there, it makes a great noise under acceleration. The car also seemed to have a little more pep in her step at speed. I am liking this so far.

It also never got to the halfway mark on the temp scale. Granted, most of the time, I was driving back roads with no traffic. This is good news though, because it tells me that this fan isn't going to run very much during normal driving in fair weather.

I dont track my gas mileage because my car isn't a daily driver, but based on the way the car was acting today, I could see how it could have a positive effect on mpg.

Now we'll see how the fan install goes tomorrow.

Side note: Thanks for all the help with suspension and shock selection. I finally found time to get the rear shocks on there, and its like I have a completely different car under me. Granted the KYBs aren't the most expensive shocks in the world, but the combo I selected, based on the recommendations her, is a nice one. Based on today's drive, I am going to be very happy with this setup.

 

[Frankenstang]

now A question on strucural integrity of the rad support. I notice that the rad is "recessed" towards the engine. can I SAFELY message it back 3/8 of an inch to have the fan fit with 3/16 of an inch to spare? or is that too close and I need more room between fan and pulley.

MPG, first those mpg numbers look REAL good, congrats Looks like you removed some decent load w/electirc fans.

As far as space limitation and the core support goes (I will be doing this myself for my clutch fan conversion) it looks like the main limitations are the radiator mounting bolts (where they protrude toward the condensor) and the hood latch support. My setup was originally a modified 'mobile aire' unit (old style generic/dealer add on non-ford specific a/c). The a/c condensor coil is still mounted in my car, but will be removed for my fan mod and engine compartment work.

However it looks like I'll need to modify the fan mounting bolts because they protrude into the space between the condensor coil and the radiator on my '66 (might use some something simple like regular bolts pointing toward engine w/stamped metal u-clips to hold in place or something more complicated like offset brackets mounted to the rad flanges). There appears to be ~1.5-2 inch of space at least between the two heat exchangers where some ground could be made up.

Otherwise looks like the hood latch support limits much more forward movement of the condensor and therefore radiator, but might be possible to notch the backside of that to gain even more ground

My rad/core support was hacked up a bit by the PO that did this mod (wrencher friend of my uncle), but I think you can do some 'careful' modification in this area w/o too much concern for structural integrity. Core support looks mainly like a bracket wall for mounting heat exchangers, front body sheet metal, etc...EXCEPT the lower portion/cross support where the the strut rod rails tie in (structural)...you could probably reinforce this are if you are concerned about integrity.

bucfan, congrats on your mod as well Looks like that procomp fan approaches the recommended cfm (IIRC 2500cfm). There's some thread here about a tempor or taurus fan mod that I might look into if my clutch fan doesn't yield desired results...I like the old school security of mechanical, but we'll see.

 

[MPGmustang]

Bucfan - what type of fan did you have before? (original 4 blade?) what t-stat are you using? isn't it more fun?
I too can't beleive the noise the mech fan was producing when I rev'd the engine, infact compared to before and after, that's all you heard on the rev "FAN"
and when you get your new electric fan, I'd like to know what's the sound level of it... 2500cfm is close to the 2400cfm I found that's 2-5/8 inch thick.

Frankenstang - your project sounds like where I want to get... lol.

Basically I'll be modifying what the radiator mounts to, moving the rad closer to the AC condenser, I too was thinking taking bolts and point them to the engine side and add nuts... making slits at the top and bottom to "slide" the rad down closer to the AC and using nuts or bolt spacers to keep it away from the engine side. then taking something to stuff in-between to restrisct air flow from going around the rad...

the hood latch is what is keeping me from mounting a pusher fan dedicated to the AC, which I'm tempted to remove and just add top hood latch locks. I wouldn't mind. I'm just courrious to how I'd go about implementing that. but I'd like to keep this as simple as possible. granted it'll be a bear to install or fix if I ever have to get back in there. while I'm installing the bigger fan I'll be adding my 100amp alt and replacing my 6 month old water pump as it's seeping from the snout. I'll try to get jegs to live up to thier warranty.

Now on a heat issue I've noticed, I really don't like the fact that my #5 & 6 cyl's head gets 240+ before the t-stat (195) moves enough water, while the front is only 190-195* during warm up. well i've been playing with the heater and I have a water valve that stops flow throught the core, as it's an all in one unit, I found that if I keep water flowing through my core, I don't get such odd temps and no temp spikes and all cyls heat up evenly. so I think I'll also by-pass my core for the summer and see how it goes, I'm tempted to add the water valve to that bypass so I can regulate how fast water flows (I don't think I need water flowing at higher freeway speeds just slow traffic)

BTW: I found a Derale fan that can push 1800 on low and 2400 on high, it's halfway to my door now, I think I'll use the low and test it out with AC, if not, it's simple to wire the high. and is still 2-5/8 inch thick

 

[bucfan1234]

Bucfan - what type of fan did you have before? (original 4 blade?) what t-stat are you using? isn't it more fun?
I too can't beleive the noise the mech fan was producing when I rev'd the engine, infact compared to before and after, that's all you heard on the rev "FAN"
and when you get your new electric fan, I'd like to know what's the sound level of it... 2500cfm is close to the 2400cfm I found that's 2-5/8 inch thick.

Yes, mine had the stock 4 blade mechanical fan. Your description of its rev sound is right on, fan rev. Oh yeah, it is much more fun driving the car and hearing the great engine noise without the clutter of that fan, especially with the duals. Up front, motor actually has a nice throaty sound to it. Who knew?

I will let you know how loud the fan is, I am going with a standard thickness fan for now. Based on my late model cars, I expect it to be pretty loud when running, but in a different way that the mech fan. The key, I hope, is that it wont be running too much.

Tstat is a bit of a mystery. I have no idea whats in it, and on a recent thread the general consensus was that, as a former south florida car, it had none. It tends to run really cool, and I dont notice the opening of a stat. On cool weather advice, I bought a 195, but I have yet to install it. I may hold of on it for now as I am undecided as to how that would impact summer driving.

I will be interested to see how your fan works out. I found them, but they exceed my budget for the fan project right now. If yours works out though, I may change mine over in the future as the Derale wound make for a better looking installation.