I need an electric fan. The one I have has three wires?

These 90 degree days have shown me that I really need a fan for traffic. I have one I feel I can adapt. I think its out of an 80s Oldsmobuick. I tested it off the battery and it works fine. If I reverse the cables, it'll push. But....it has a third wire to a ballast resistor. Do I need this? I'd hate to hook it up and fry it with twelve volts. Anyone know about this stuff?

 

I don't think you will fry anything :TU:

 

I think those fans had a low-speed input. If you feed 12V to the resistor, I bet the fan goes slow. Then feed power to the non-resistor circuit, the fan will probably go faster.

Just a guess.

-Bob C.

 

thats my guess also,the one without resistor is for driving & the one w/resistor is slow speed for cooling after shutdown.

 

i'll also put in a theory. the resistor one is for when the air conditioner is on and the full power to suck the heat away from the engine.

you could set up two thermostats for dual speed fans, or if you have AC can set up a relay to turn on the one with the resistor when the compressor magenetic coil is turned on.

nate

 

I thought of that today. Maybe it being A/C related. I also acquired some Neon fans today. Much smaller. One of these is going in. Thanks guys!

 

I know you guys are suffering with 90 degrees up there-- LOL-- but you can fix your cooling problem without mods if you want to keep it stock.

Most likely it's your radiator. Everybody waits til the last thing to change it because it's the most expensive, but that's usually what is the problem.

 

I got a big ole four core in it. Its fine at highway speeds. Its always had a tendency to get hot if I get stuck in traffic. Now with the mods it seems to heat up quicker.

 

Have you looked at a twin fan setup like off of an Intrepid. They're supposed to be very compact and flow tons of air. And they're dirt cheap since the cars aren't very popular. Ferd Taurus fans are another one that flow a lot of air.

 

In that vein, the Lincoln Mark VIII fans are said to be the best.

http://cgi.ebay.com/ebaymotors/2-Sp...015QQitemZ250271910551QQrdZ1QQsspagenameZWDVW

 

True.

 

Hmmm......I'll hafta check into that fan clutch. Right now I'm idling 'round 28. Its about half timing and half vacuum advance with stop. I do suspect the fan clutch may be week, since most of my stuff is old. But I figured a free electric fan will be cheaper than a new clutch. Still, I'll check that part # out. Thanks!

 

Won't the legs in that Ebay Radiator cause a problem installing it? :laugh: :laugh: :eek2: :eek2: p

 

Big electric fans pull considerable amps. Hope your alternator is upgraded. Stock or heavy duty stock for original design won't keep up for long. The Ballast resistor is to run at slow speed and/or when a/c is running. High speed is other wire and third wire is ground. like most say the lincoln fans are the hot item (pun intended)p .

 

For the 3 wire fans, how would you wire it ? I just recently got my hands on a 2 fan 1 piece, (12 inch each), setup from an intrepid. How and what should i wire these too ?

 

http://www.lextreme.com/relay.html
http://www.the12volt.com/installbay/forum_posts.asp?TID=80936&PN=1
o No:
http://images.google.com/images?sou...&sa=X&oi=image_result_group&resnum=1&ct=title

There is a 1/2 dozen ways you can wire an electric cooling fan. All I can say is it better be reliable or you are going to COOK an engine. You will need a temperature sensor if you want automated control.

Have you ever wired a set of fog lights, electric fuel pump, or a horn with a relay before? It's real similar to that.

ElectraJim

 

Yes, i wired fog lights before. this is a three wire hookup. So i'm guessing i need to get my hands on a SPDT Relay before trying to hook this up? have any three wire diaghrams ?

 

Dan, could be a slow turning water pump.... a large pulley on the water pump and/or small pulley on the crank could cause excessive heat when idling.

 

Best bet would be find the OEM application that the fan you have is designed for.
Find out what wiring (from that application) is used to power the fan. If it's a 2 speed or whatever.
My GUESS is that one terminal on the fan is a ground, and the other connection may be for a slow speed, and the other is high speed.
Think of the wiring on a 1157 bulb.
You'll have to bench test it to find out.
You can also go to a salvage yard, find a similar fan with the same connectors, examine THOSE wires connected to the fan. Those may tell a story on what those fan terminals actually are. I'd take the connector with the wires if you find one.
I don't think anyone here is able to tell you exactly what wire to hook to which terminal on the fan.

Good luck, and watch your fingers.

ElectraJim