fan power..when and how? Magnum FMIC

spetz01

Registered User
I installed a new 16" fan when I put in my new IC.


The original has 3 wires, the new has 2. The instructions say to cut off the original fan plug and splice to the new fan, black to black and red to red. So that leaves one wire.

My problem is I cut the original fan plug to short to splice...But whats the difference if the third wire is not connected on the fan side?

So when does the car send a signal to the fan to tell her to turn on? And whats the third wire for?

Right now I have an under the hood switch to turn it on and off but thats lame.
 
Old fan had two sets of windings, one for high speed one for low. I'd want to tie both of the power wires together if using them for power since the stock system shuts off the low speed when it gets really hot and turns on the high speed.

So if you wire to the high speed, you don't get anything when the fan would normally be on. If you wire to the low speed you loose fan when it gets really hot.

Any after market fan (and I'm doing one) I'd get the thermostatic switch from the fan company. That plus a relay and you can pull power right off the battery and control the fan properly rather than relying on the EEC.
 
I don't know if this is too far off subject, but I've had the #14 wire cut on my ircm so the low speed fan will run continuously and lately the fan seems louder, like maybe the high speed is running instead. Is it possible that the low speed has quit and the high speed is now coming on? :confused:
 
Fan

I used to run my low speed fan all the time, (cut #14 wire)but I pooched the fan after awhile. So your fan might be on the way out. To check if your fan is working on low speed or high, turn your car on and watch/listen to the fan and then have someone turn on your A/C. The high speed circuit should kick in and you'll see/hear the difference in the fan if it's working properly. Also when your high speed fan is working, and your at operating temperature, you should see the Temp gauge go down a bit.

JT
 
That would work, except The only thing on the car from the ac is the compressor, the rest has been removed. I'd guess it's on the way out too. I had been planning to wire a switch in for the fan, but never did.
 
Fans/motors

FYI my stock 2 speed went out also. Went to the junk yard and found a 2 speed on a Tarus, took fan and shroud. The shroud assy. would not bolt up so I put the tarus motor in the SC shroud. Then SC fan would not fit because the motor/shaft combination was a different shorter length. I put on the Tarus fan which was a slightly smaller diameter than the SC. That combination worked well in temperatures to 110 degrees with the air on no problems.
 
Most likely your fan is dying if it's starting to sound different. I'm planning to mount two Perma-cool fans on my griffin radiator in the 93. One pusher, one puller.

I ordered one, but then saw some CPU cooler reviews and noticed they are able to get better cooling with 2 120mm fans on some of the better heat sink designs. I figured I'll run two, one that turns on at a 180 setpoint, and another that turns on at 200. Likely overkill for a stock motor, but mine won't be stock.
 
The MP instruction actually say to take the two power wires for the fan (high & low speed) and join them together, then couple those two wires to the red wire on the new fan, and attach the remaining wire (ground) to the black wire on the new fan.

The way you have it wired won't work correctly. If you used the high speed wire then the fan won't come on until something like 215 degrees...if you used the low speed side it will work fine unless you reach 215 then low will shut down and you won't have high speed.

David
 
I've got it right now...Two wires connected to the red and black to black. I ran it in the driveway for a bit and then it came on...ran for about 30 seconds and shut down. That SPAL fan moves so much air.

I guess this cools down the IC enough?
 
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