Mark VIII Fan + Aluminum Radiator + 5.0L?

[slow84lx]

Wiring the fan as a 1-speed is overkill if done on High only. The fan on both of my cars normally ran on the lower speed until doing stop n go traffic or the hotter days of summer.

I have a friend with a classic Mustang who runs a Contour fan. Fits his car well and works very well also. Lots of guys having success running the Taurus fans also.

[ZephyrEFI]

Yeah, I think the shrouds, fan blades, and everything are all the same, all years, so a replacement motor would fit in any year unit.

Well, I'm just thinking 1-speed in case the later ones are, in fact 1-speed only. I've seen information both ways. Interestingly, I saw a diagram that states that the later motors do have 3 pins (in the female connector on the motor itself), but the middle one dead-ends in the connector. If that middle pin is for low speed (which i think is what you're getting at), I could use that with an earlier connector. I'd have to rethink my relay setup though. Maybe i could use one of my 70 amp relays for the low speed and get one of those solenoids for high... If that's the case though, why doesn't anyone i find online wire it that way? All I've found are these complex setups with multiple relays and resistors and stuff. I even found a guy that wired his as a 4-speed! Anyway, here it is both ways. Of course, i have no idea if these are from actual EVTMs or not. The font is pretty fancy, haha.

[Haystack]

I ran a taurus fan two speed and liked it alot. I ended up wiring to a switch cause i kept burning up speed controllers. Only time i used high is when i forgot to turn on the low speed. It was adequate on low pretty much always, though this was on a car with 300+k miles. Not souped up or anything.

[ZephyrEFI]

Yeah, that's an option too. I just started with the most crazy high speed fan because of the Hose Wizards guy's warning about big radiators affecting air flow through the condenser.

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[ZephyrEFI]

Well, I bought a '97-98 Mark VIII fan. But we all saw that coming, didn't we?

So now, I'm needing to figure out how to run it. I looked up the Echlin ST34 solenoid, and I notice it says on Napa's site that it's a "starter solenoid". Does that mean that any starter solenoid would work? After all, I already have a couple of those.... Although the site doesn't list any specific applications for the ST34 that I could find. I don't imagine most starter solenoids are "continuous duty" since they only engage while cranking the engine, but I don't know enough about solenoids to be able to say one way or the other.

[Haystack]

I dont see why a starter solinoid would'nt work.

My problems with the cheapie fan controllers was actually the fuse holder crimps on the controller. I thought they were all burned up cause i couldn't them to do anything. I cut the fuse holders off thinking it would save me effort later on, along with the cheapie 40amp relays. I ended up wiring them straight up to a switch using the relays with a switch to trigger them. The fuse holders were junk, ended up using just some crimp connectors straight to the fuse, and never had another problem.

As long as you start up the fan on low, you really only pull 20 amps or so on startup, 16 amps when settled. If you have the equipment to test it, id be interested in see the numbers. From a dead stop to the high, it pulls 36 amps for less then a second and settles at about 20 amps on my setup.

[erratic50]

Why not wire the big relay of your favorite type to a signal lead that turns it on (so you put power to the fan) only when the key is on. Add the Coolant temp sensor in the route would keep it off when you first start the car. Heck, even go two speed. Seems about perfect.

[Haystack]

Thats the way i would probably go now. I initially had it fail and had to fix it in the side of the road a few times, that's how i ended up with the switch.

The switch is cool through because you can run the fan if the car is off.

[ZephyrEFI]

That's the thing though, i don't know for sure if that fan HAS low! I do have a multimeter with an inductive pick-up. So when i get it, I'll run that test and let you know.

I may do the resistor thing and create a "low" if it doesn't. We'll see.

[Ethyl Cat]

That's the thing though, i don't know for sure if that fan HAS low! I do have a multimeter with an inductive pick-up. So when i get it, I'll run that test and let you know.

I may do the resistor thing and create a "low" if it doesn't. We'll see.

The Mark VIII had a VLCM that could control the fan speed but the fan only has 2 wires.

[slow84lx]

That's the thing though, i don't know for sure if that fan HAS low! I do have a multimeter with an inductive pick-up. So when i get it, I'll run that test and let you know.

I may do the resistor thing and create a "low" if it doesn't. We'll see.

The fan, as factory installed & wired, is a a 2-speed fan in all years Mark VIII.

The trick will be to wire it that way on your car.

[ZephyrEFI]

The fan, as factory installed & wired, is a a 2-speed fan in all years Mark VIII.

The trick will be to wire it that way on your car.

Well, as it turns out, the guy I'm buying the fan from doesn't have a 2-wire connector at the moment, so he's sending me a 3-wire. I hope you're right, it would make things a lot simpler.

[ZephyrEFI]

I have an mn12 T-bird fan on my Capri. It was some work to do, but it turned out nicely. I had to router 1/2" off of the shroud to make it fit, and make my own mounting brackets out of aluminum and rivet them in place. I have a Volkswagen 2 speed fan switch screwed into an adapter in my upper radiator hose that controls 2 relays to actuate either high or low speed. I put a rocker switch in the glove box that turns the ignition 12v wire on or off going to the relay, and if I go to the strip I jumper the plug at the switch for manual control. I originally did this on my dd Dakota years ago with the same model fan, and I'm still using that setup to this day. The only difference is that my a/c and defrost settings trigger the low speed setting of the fan as the Capri doesn't have a/c. I looked, but I don't have any pictures of the setup.

Wiring:



Cale

I took another look at this, and it's not in parallel, is it?

Now, i guess I'm strongly considering a DCC controller. I've read a lot of stuff on forums, right or wrong, who knows, but I've read running this fan at full speed too much can burn up your fan motor. My concern there though, is will it run the fan fast enough to pull enough air through the condenser to cool properly, since it varies the speed with pulse width modulation. Right now, i have my fan set to come on at 205 on low and 210 on high, which is higher than most typical controllers meant for race cars. I like to set it high enough so that it's at the temp the EFI expects for maximum efficiency. I know the temp is adjustable on the DCC, but... maybe I'm just thinking too much. I do that. Anyway, I've read plenty about melted relays and harnesses with this fan too. It's at least a comfort that the DCC controller was designed around the Mark VIII fan...

The fan arrived today. I'll test it today or tomorrow and report back whether that middle wire does anything. There are a few videos on youtube with people testing "mark viii fans" but again, who knows if they're the early ones or not.

[ZephyrEFI]

Here's the fan. Look at it. In all its glory.



Going back to the original purpose of this thread, the shroud will definitely need to be cut down for thickness.

Apparently the poster of the fan sells several and forgot to update the fact that this one would come with a 2-wire connector.



Shroud has an "F7" part number on it.



It's actually fine that it's a 2-wire connector because I managed to sell my old controller (sad to see it go. I liked it a lot), so I've ordered the DCC FK-45. I thought about trying to create a way to do low and high speed using resistors and diodes and stuff, but I think i was just in over my head. Then you add not wanting to run the thing on high too much, and it was just not worth the worry. This greatly simplifies things. Hook it up and go. No worries about whether it will work or last or anything like that. Seems to be my theme lately. Spend more money and everything will be fine.

[ZephyrEFI]

Wow, THIS is wicked cool!

https://www.stangnet.com/mustang-for...it-out.755550/

Mounting your fan inside the factory shroud! I'm sorely tempted to do this. I'm a sucker for a stock look!

Look how nice it could fit!

[Ourobos]

^ Since the fan is backwards with the motor towards the radiator, I guess wire it backwards as well for a puller?

[ZephyrEFI]

^ Since the fan is backwards with the motor towards the radiator, I guess wire it backwards as well for a puller?

haha, no, that's just to show the size comparison. There's pictures of what the guy did in the link. I WOULD have to track down a stock shroud though. Which I don't really want to do...

[ZephyrEFI]

Started looking at cutting down my shroud to fit. Hot Rod claims they were able to cut theirs down by 1 1/4".

http://www.hotrod.com/articles/1005p...ooling-system/

But, when i measured on mine, if I cut mine by 1" I'd have contact between blades and fins! Ran out of time before I got to cutting, but if you're looking to do this, better check for yourself! You can easily measure by setting a straight edge on the face of your fan, then looking at where it ends up at the edge of the shroud.



I'll report more once i do the cutting and then put the fan in place as far as fit.

You might've seen elsewhere that I tried testing my fan by running jumper cables to my battery with the car off and it didn't come on. I was speculating maybe there wasn't enough amps with the car off to start it up, or maybe the jumper cables weren't any good or they weren't making a good connection for whatever reason. I also had a guy tell me maybe the motor is brushless and therefore doesn't like direct current, but I'm not so sure of that. Either way, i hope to hell I don't have a bad fan on my hands. I'll try testing it again with the controller when it comes.

Speaking of that, I ordered the DCC controller 2 weeks ago now. I emailed them last week to get a status update, not being accustomed to not hearing anything from an online company like that. Not even a confirmation. They responded and said they will let me know when it ships, and that should happen this week. Sounds like they must wait until they get an order and THEN build it. Anyway, thought you might be interested if you're looking at going that route that your customer experience will be a little different from the norm.

[slow84lx]

I'm enjoying this thread and following this installation as I want to do a similar install on my '84 coupe down the road. I kept the fan & shroud from the '93 Mark VIII that I parted out just for this reason but have not yet installed. Keep us posted.

Jonathan

[ZephyrEFI]

Will do!

[cb84capri]

I took another look at this, and it's not in parallel, is it? t.

What are you talking about?

Cale

[ZephyrEFI]

When I first looked at your diagram, I thought your relays were wired in parallel. But I see now that they aren't.

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[ZephyrEFI]

Woo! My controller shipped!

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[Haystack]

Im curious how it all works out. You dont have anything to measure amp draw do ya?

[ZephyrEFI]

Im curious how it all works out. You dont have anything to measure amp draw do ya?

My multimeter has an inductive pickup, but I've never used it.