Electric Fan wiring

[BrockGrimes]

Gentle folks preferably wiring guru's does this electric fan wiring scheme work?
Any changes recommendations? I could also just use a lighted switch instead?
5amp fuse for the 12v ignition side?
Fusable link or 30amp fuse or bigger?
10-12 GA for power and grounds
12-16 for others?

[Nitekruizer]

What is the object in the upper right corner of the diagram? Is it a second fan motor?

In order for the fans to run automatically, there would have to be some type of temperature sensor in the circuit.

Also, what is the purpose of the indicator light? Is it just to show that the "Manual Override" switch is in the "On" position or is the light supposed to come on whenever the fans are running?


From your diagram, the way the circuit is set up, it could work if you just want to operate the fan(s) manually. Depending on how much current your chosen fan motor draws, I would make sure that the relays are at least rated for 40 Amps each and use a minimum 10 Ga wire for the power circuits. I would prefer 8 Ga wire, but the problem is finding terminals that fit. I think you will likely need more than a 30 Amp fuse.
You can use 18 or 16 Ga wire for the trigger circuit to the relays, the "Manual Override" switch and indicator light.

[BrockGrimes]

Sorry the thing in the top right should just be a switch. (not my diagram)
Basically, I'm looking to run a single fan that will run when the key is on.

I'm not trying to be fancy and have it temp controlled and all that just on while it's running.

Would this be a better setup?

[Nitekruizer]

OK. It should work if the relays and wiring can handle the amperage drawn by the fan motor. The way the indicator light is wired in the first diagram won't work (the light is already grounded through the "Manual Override" switch). The grounded side of the light should be wired to the main positive wire at the fuse link. That way the light will be lit whenever the switch is "On".

[Nitekruizer]

The only problem is that I think most of these fan motors, except maybe for the very smallest fans, pull more than 30 Amps.

[BrockGrimes]

Yeah was trying to research an easy way to wire it up. I might just stop by autozone and pick up a fan control/wiring kit.
The PO installed the fan with it just hotwired right into the fuse box, literally a spade plugged onto a terminal.

[aquartlow]

If you are going to use relays for the fans(wise choice), I would highly recommend 70 relays over the more common 30/40 amp relays. An electric fan doesn't draw a tremendous amount of current while running, but the start-up spikes will kill the smaller relays rather quickly. Here are some I use on a dual cooling fan assembly I use on my 466 Ranchero, cools really well with no electrical issues. I had previously upgraded to a 130amp 3G alternator, which easily handles the increased amperage output needed for the fans.

This shows the difference in terminal size between a 70 amp relay (left) and a standard 30/40 amp relay.


Here are the controllers I used(one for each fan), they are adjustable and have a temp sensor that installs into a 3/8 NPT opening.


Good luck in whatever you choose. Todd

[HIO Silver]

For your info:

Ford Muscle: Lincoln Mark VIII Retrofit
Fordification Thread: Lincoln Mark VIII/T-bird Two-Speed Fan Installation
Pro-Touring.com Thread: Mark VIII fan & SPAL Controller
Hollister Road Electric Fan Components
The Fan Man - Electric Fans & Controllers
Nasty Z28 Thread: Budget Dual Electric Fan Controller Set Up
FTE Thread: akforceten's 1972 F250
Centech Fan Controllers

[BrockGrimes]

I decided to just hit up autozone and grab one of the universal types wiring kits with the temp probe that goes in the radiator fins, not ideal but it'll work for now.

Another link you guys might be interested in: http://www.musclemustangfastfords.com/t ... n_upgrade/
Another thread about it: http://www.cherokeetalk.com/forum/f9/ge ... read-7828/
I have been a jeep guy for years and the Ford Taurus/Mark VIII fan have been getting slim. Turns out the Contour dual is a better fan and usually fits better.
There are two types the one your interested in is the one with the built in shroud. It'll cover more radiator.
You'll have to check out that thread but it's got the info there.