Electric fans from the junkyard

[Var]

So i went to the junkyard and bought some electric fans. I got 4 fans for 45 bucks. My setup right now is a Koyo rad with a Z32 auxilary fan. this setup isnt enough for my cooling needs cause the temp needle likes to creep to 3/4 sometimes more. So i got these 4 fans just in case one or two of them doesnt work or doesnt have enough airflow. But then i thought maybe i could put 2 in front and 2 behind the rad and wire them to pull/push properly. My question is what would be the best way to wire these fans? my current setup is wired to a switch with no relay or fuses..yeah it's dumb but it wasnt supposed to be permanent. I was thinking of running a separate 20amp fuse for each fan but hooking them all up to one switch with no relay. What do you guys think?



i'll hook up the fuses through a simple panel like this one

[statik]

get 2 relays and 2 thermo switches, set one thermo to kick on the main fan when it starts to get hot, set the other thermo for when things get hotter and have it kick on the second fan, ok so maybe spending $80 on thermo switches is defeating the purpose of buying fans from a junkyard, but it'd be cool =]

[projectRDM]

There is no way you need 4 fans. The OE temp gauge is highly inaccurate, if anything you've got a sticking thermostat and that's why you're seeing higher temps. I'm currently running with no fan at all and can sit in traffic for several minutes before breaking 200 degrees. Normal driving it never passes 180 degrees. There's another problem somewhere if you can't keep the temps down with what you have.

Running all four fans without a relay is going to load the switch too much and burn it out, it's uncommon to find 100amp SPST switches for automotive use. Some OE fans can pull up to 40amps. Plus the load on the battery will kill any sort of gain you might see, the fuel pump will see a voltage drop and force the car to run lean anyway, making it run hotter than it would. A single fan is more than adequate if mounted and shrouded right.

[statik]

also, what he said ^^

[Var]

What he said doesnt make sense...if my engine is revving @ 4-7500 rpm, you're telling me my alternator wont push enough current to run the fans and it will lean out my engine? what about people that run 2000 watt stereos in their cars? Do their cars run lean too?

[projectRDM]

Yes.

How lean? Very little, but there's still no reason to use four fans when one can do the job, and the amount of wiring, relays, and switches will be more than required. Plus amplifiers pull different loads depending on volume and musical transients. When a car with a large system sees a dynamic, the headlights dim, correct? Under a load, the headlights and fuel pump are pulling the most current, some of that is directed to the stereo system to compensate. With a total of four fans running and pulling upwards of 100amps all the time, the alternator will have to work very hard to keep up with everything because it's a constant load. If you want to run all four, by all means go for it, but there's simply no reason to. You'd see cooler temps by gutting your thermostat and not even running a fan than you would running all four.
You asked what we think, you can choose to believe or ignore any or all of it. It's called an opinion.

[Var]

Ok ..i'll try gutting the thermostat. And i'll run 2 fans. Thanks for the advise

[tastyratz]

yea dont run 4 fans... run 1 good one. anything else see the rest of your system. thermostats are 10$ or less so just buy a new one you dont have to gut it.