keeping elec engine fan on constantly???

[Muzzy]

how do i trick it to do this...(i know i have seen this some where before)and yes i am stepping up to a dual fan and dropin the one on the motor.

[the head]

wireing will be there just leave out the temp switch to turn it on and off it will just be wired to a toggle on the dash instead also good to run it to an IGN switched power source that way you won't accidentally leave it on and drain your battery

[uiuc240]

Originally posted by the head
wireing will be there just leave out the temp switch to turn it on and off it will just be wired to a toggle on the dash instead also good to run it to an IGN switched power source that way you won't accidentally leave it on and drain your battery

That's a BAD idea. I had mine wired to a switched source, but the wiring is too small for the fans (they pull nearly 20 amps). I now have it wired directly to the battery (through the included thermostat switch) and it's been working flawlessly for over a year. Running directly off the battery made an OBVIOUS difference in the fans' operation. They immediately pulled harder and louder.

Eric

[Muzzy]

u said the wiring is to small??
so did u change the gauge of wire??
u hard wired it to your battery...how do u turn off?
wut thermostat switch theres no wires connected to it?

[Steeles]

yup you'll burn the wiring. thats whats happened to mine. I need to redo it. I gotta tap into whats left of the starter harness since the battery is in the trunk now.... I'll redo it when I get a new radiator... sometime this month.

[the head]

wire the toggle to control a bosch style relay under hood then wireing wont burn i have used it before forgot to explain relay last night i was very tired
you can make your own setup with a relay or you can buy a fog light wiring harness at the auto parts store make sure it is one that comes with relay and easy instructions are provided in those kits

hope this helps

[uiuc240]

Originally posted by Muzzy
u said the wiring is to small??
so did u change the gauge of wire??
u hard wired it to your battery...how do u turn off?
wut thermostat switch theres no wires connected to it?

If you tap into the engine wiring harness to a switched (IGN ON) wire, there really aren't any that will handle the current of these fans. 20 amps needs at least 12 gauge wire. the wiring that comes with the fans is fine. just run a power wire direct from the battery post to the fans. the thermostat incorporates a relay that completes the GROUND circuit. that's how the fans turn on/off. whenever the thermostat is in the "open" position (it's an adjustable doohicky just like in your house) the circuit is not completed and the fans stay off.

Here's one example:



Here's another:



Mine looks a little different than both of these (cheaper). I think when I redo things under the hood, I'll replace it with one like the 2nd image.

Eric

[uiuc240]

Originally posted by the head
wire the toggle to control a bosch style relay under hood then wireing wont burn i have used it before forgot to explain relay last night i was very tired
you can make your own setup with a relay or you can buy a fog light wiring harness at the auto parts store make sure it is one that comes with relay and easy instructions are provided in those kits

hope this helps

A relay does not magically change the way electrical current works. 20 amps is 20 amps. A relay, like the one shown below, simply directs current and allows you to switch things on and off without running all that current through the switch. A 20 amp toggle is *expensive* and *dangerous*. A relay does NOT change the fact that you're trying to draw 20 amps of current through 16-18 gauge wires (which max out at about 7 amps).

Learn yourself.



Eric

[the head]

then theoretically the wires on the fan would melt also the lower temp switch you posted is nothing different from what i am talking about the only difference is that you would have a toggle instead of the thermoswitch (little silver box) no other differences in wireing just another form of activation

use the ign in series with the toggle to energize the coil on the relay not to power the fans yes you tap power directly off the batt for juice i am just talking how to turn them on

grew up on this stuff and learned a long time ago

[uiuc240]

Originally posted by the head
use the ign in series with the toggle to energize the coil on the relay not to power the fans yes you tap power directly off the batt for juice i am just talking how to turn them on

ok, there you go. now i know you understand. gotta make sure the other kiddies do too.

cheers,
Eric

[the head]

i have done this stuff long enough that it is hard to explain i leave stuff out

gald i got my point across

[andrave]

A relay does not magically change the way electrical current works. 20 amps is 20 amps. A relay, like the one shown below, simply directs current and allows you to switch things on and off without running all that current through the switch. A 20 amp toggle is *expensive* and *dangerous*. A relay does NOT change the fact that you're trying to draw 20 amps of current through 16-18 gauge wires (which max out at about 7 amps).

\

You guys understand that a relay is like a big, remotely controlled switch, right?

Its not clear from the above posts that you have a thorough grasp of how exactly they work. a relay uses a small amount of current to attract a magnetic pickup which completes the connection.

you CAN run 18 gauge wire to the switch which controls the relay , you just have to run the correct (12 gauge) size wire to the relay (from the battery to pin 30) and from the relay to the fan (pin 87).
Ground pin 85 and run positive current through a switch and into pin 86.
That way current flows through the switch when its on, into the relay through pins 86-85, closes the switch for pins 30-87, and completes the circuit.

Anyway, at any rate you should ALWAYS be fusing any wiring you add to your vehicle, otherwise wires can burn.
when a fuse holder costs 2 bucks at advance auto, why would you even want to gamble without it?

[uiuc240]

yes, Andrave, we understand that.

I was simply saying that you can't just tap in to a 12v IGN ON wire on the harness. It's not big enough for the fans. I know how relays work. What I was saying before is basically exactly what you said (you said remotely controlled switch, i said "redirects power"...whatever)

That was a good post for those that don't know, though. nice.

Eric

[Muzzy]

AAAHHHHH!!! WTH!!! i guess i have to see every with my own eyes inorder to understand it better...i think i'll understand better when i get my new fan.

but thanks for the help though

[andrave]

my brother got a new "imperial" fan from autozone for his turbocoupe and it came with all a relay, some wiring, and the wiring schematics, so don't stress too much.

[Muzzy]

andrave: dual or single fan and how much???

[andrave]

his was a single 16" for 70 bucks. the current draw is a little higher than some, I think its 22 amps, but for the price it was a good deal.

[95Blue240sx]

there is a much simpler way to do it. there is already a relat for the fans in the engine bay. and all you have to do is tap the wire that switches the fan on and off to ground with a switch in between. similar to the one on www.240sx.org IMHO this is the best setup. you can turn the fan on manually or just let the coolant temp switch turn it on. but i believe if you dont switch it on manually the computers switches it on like around 220* normal operating temp is ~180-190*