How to wire up an electric fan?

[RockPaperSwoRD]

I want to run a ford taurus E fan on my car, its commonly used because it pushes alot of air for a stock fan .
my question is if I take off the twin AC fans, and combine the two separate leads, could i use the combined power to power a the 16" fan?

does anyone know if it will turn on to cool the engine or only turn on when the AC is on?

 

[oldsking]

It does turn on once your car reaches 210 or when the AC is on.. I would wire it on a switch if I were you

 

[OneJArpus]

When you go with an E Fan setup, i would personally wire it all up with brand new relays, wires, and such.

 

[te72]

x2 on the switch suggestion. Wiring is probably my weakest point when working on a car, but even I was able to figure it out with a bit of advice.

 

[NashMan]

relay and running full time is the best and have it on switch so it easyer to start in the morning

plus it is the cheapest way

 

[grimreaper]

Id get a thermo switch. You'll get to 210 quick with out air flow in the heat + AC usage.

Make sure theres a fuse between he battery and relay, wire size needs to be considered as well as current draw. Its a complete system and should be treated as such.

 

[Alec]

Anyone know the positive leads for the foglight switch? I'd like to wire the AC fans to the foglight switch since I removed my fogs anyway. Wiring it should be pretty easy once I find the positive lead for the foglight switch, http://www.supras.com/06/techcenter/display.php?QID=37

 

[limequat]

I'm currently running this fan in my Supra. The stock wiring for just about any circuit is not going to cut it. The wiring to the condensor fans is on the order of 18AWG.

Here's how I have mine wired up:
10 AWG wire off of 60 Amp fusible link to high speed power.
10 AWG wire from fan ground to 30/40 Amp Relay from Summit (< $5)
The relay ground is then connected directly to the battery negative.
I'm currently not using the low speed setting, so that wire is left open.
Relay is controlled by my PCM, but you can get cheap thermal switches to do the same job.

The taurus fan has massive transients on power on. People have measured over 70 amps. This is why it's important to put the relay on the negative side, as constant current is more like 30 amps. You need to have a fuse or fuseable link on the high side so you don't burn your ride down when you accidently short the battery to the core support

Don't rely on a switch to activate your relay. You forget, or someone else drives your car and you banana your head.

 

[GrimJack]

I also tend to wire the relays so that when something fails - the signal to turn on, for instance - the fans come on by default. I don't like the idea of a system where a fault leaves you without a fan.

 

[limequat]

I also tend to wire the relays so that when something fails - the signal to turn on, for instance - the fans come on by default. I don't like the idea of a system where a fault leaves you without a fan.

Good point, though I think not always possible.

If you have the intestinal fortidute, OEMs generally use at least one more relay than devices they're driving. Stare at a schematic for -say- a maxima for long enough and you'll realize that any single point failure will have a neglible effect on the system.

GM does some cool stuff in software (free). They can check for a failing relay by monitoring its output voltage. If they detect overheating or low oil, they'll put the engine into a reduced power mode.

 

[GrimJack]

Good point, though I think not always possible.

If you have the intestinal fortidute, OEMs generally use at least one more relay than devices they're driving. Stare at a schematic for -say- a maxima for long enough and you'll realize that any single point failure will have a neglible effect on the system.

Exactly the kind of system I like to replicate.