Electric fan setups and temp settings

[pr240sx]

just a reminderthe stock temp neddle only has 3 positionscold, operational, overheat.Dont try to compare or use the stock temp gauge as an exact measurement. Use a external gauge or a code reader (Multichecker, MDM, etc)I have an Altima fans setup on my S13. One speed is controlled via an adjustable thermistor and the other via ECU/AC control. My temps NEVER go past 200.Also, for those who want a lower temp, instead of using a thermostat, you can run a water restrictor.

[Jookmasta]

which thermistor are u using pr240sx?

[DammitBobby]

Could you give more info on your setup for the adjustable thermo? I am guessing you just plug the other fan into the stock ac adapter with no modification?

We need a right up and add this to the sticky.

[pr240sx]

First thingAltima fans (the ones I am using) have 4 wires each motor.2 positive 2 negatives. You need to energize both for high speed, one set for low speed.So:If youwant to use the fans as a set you will need good wiring (no less than 12gauge) to extend and connect the 2 circuits. You will join 4 wires so you will end from the original 8 wires down to 4.Now, you will need to decide how do you want your fans to turn-on. I decided to use an adjustable thermistor (purchased at Pep Boys). Wired a relay and use GOOD WIRING PLEASE!!For reliability, I used the thermistor to activate the relay then the fans. As for the other circuit, I wired to another relay to the stock A/C connector. Remember these fans draw a lot of current! In my case (s13) the stock AC fan is single speed. On a S14 you can send the other circuit so it will activate the high speed circuit without the thermistor (another relay!)I even kept the stock AC fan motor around just in case (not installed of course).Will take post pics of the process from back then.Recomendations:Use good wiring and use fuses or circuit breakers. You can never overprotect a circuit.Plan ahead your wiring, I went to the jukyard and got several fan connectors. My install looks almost stock and works excellent in mid 80 to 110 temps ( I live in the tropics)The hardest part is setting the thermistor temp right. Most thermistors are the radiator "poke" type. I plan to use a water temp (more precise)The activation temp will not be the same if the hood is open or the car is running. Here is where a good temp gauge comes. If the ECU sensor "sees"an overheat situation (more than 202) will activate the fans, retard timing in some cases, raise the idle speed and dump more fuel!I used a MDM-100 for this.

For those who want to yank out the old noisy mech fan, get Altima fans. Cheaper and they look good and stock.I am now turbo and the temp differences are minimal WITH STOCK RADIATOR and a water restrictor (no thermostat)Will gladly ask questions so please feel free to contact me via email or for forum help sake post your questions here!![email protected]
Modified by pr240sx at 7:47 AM 12/6/2005

[rn240sx]

he isnt accessing that part of the code at this time. i guess there is no way then to change the temp when the a/c fan will kick on unless u get some kind of thermal switch.....

Well, nissan programmed it to work that way. Jim wolf's primary tech that does the tunning was a previous NISSAN tech that did all the ecu programming FOR NISSAN...

That is why he knows how to re-map the fuel and timming. Im sure he knows how to do it, but since the demand is ZERO for that feature, they wont even bother messing with it..

[240DRFT]

pr240, could u use altima fans and a three step switch for off then low then high?

[pr240sx]

Never seen a 3 step switch and dunno how it works.Assuming that it works just like and relay with 2 different switched outputs it may work.

Do your install in paper and then do the actual wiring. Way easier and cheaper than trying to fix a flawed design.

[240DRFT]

its just a switch that instead of on or off there's on, then middle, then off.

[pr240sx]

Sure, but if you want to use the dual speed function of the fans, both circuits needs power.Any circuit.I personally think that relays are easier to work with rather than triple switches, but thats my opinion. Check the amp rating on that triple switch. Alti fans draw a lot of current when turning on.

[KATwo40]

Dang, ya'll make this very complicated.

I used twin fans, one on an adjustable thermostat (purchased at your local A-Zone with temp probe attached to radiator) and the other on the stock condenser fan circuit. Neither is running all the time, and both turn on at appropriate times.

In fact, now that it's cold (30-50F...depending on time of day), the primary fan rarely even turns on (WOOHOO KOYO 2 ROW!). And in warmer weather, the fan runs until the coolant reaches shutoff temp, even with the car off.

Very simple, no need for ghetto @$$ things like leaving the blower motor and a/c buttons on.

[Fenvy]

didn't read most of the thread but regarding the author's post, hot wiring directly to the harness might not be a good idea. I would use a relay before that.

[rn240sx]

i recently was driving around with a snapon scanner in my car and was watching the coolant temprature. Normal crusing around town was 176-178 degrees. Highway at 70 mph, 174-175 degrees for about 10 miles. Sitting still at idle 8-10mins the temps never went above 191. Snapon scanner with factory '96 coolant temprature sensor. Factory Radiator, factory mechacical fan w\ shroud inplace. 70% water\ 30% coolant. Out side temprature was around 82 degrees, with a 30x10x3 (core) spearco FMIC blocking direct airflow.

the A\C was off while i recorded the numbers and there really wasnt much change in tempratures, maybe +2 degrees around town.

I hate to bring this back from almost 3 yrs ago but i read what u wrote and i find it funny that my results are the EXACT opposite of urs....

I have the stock 98 ka radiator, stock thermostat, 50/50 pre-diluted antifreeze, dual 12' flex a lite fans and small fmi 24 x 6 x 3.5 Each fan is wired to its own fuse and relay with one adj therm set to kick on at 180F...

Sitting at idle for 10-15 min ( NO AC ) my water temps cycle between 165-183. Thats from the fans comming on at 180... then cooling down to 165 and shutting off. Cycling like this over and over... providing that i do NOT move....

Cruising at 40mph ( 10+ min NO AC ) my water temps reach ~190 and stay there as long as i am moving.... fans are on the entire time.

Cruising at 60 mph ( 10+ min NO AC ) on the hwy my water temps reach 200F and stay there solid the entire time.... and the fans are running the entire time.

Speeding at 80 mph, same results as above... 200F and holding there solid.

The ONLY time my hwy temps dropped below 190F was when the outside temps were 50F and below....

Obviously there is an air flow issue at hwy speeds for my setup, but urs is completly different......

[ghx407]

I'm in Puerto Rico and it's freakin' hot here. I got a stock radiator, stock thermostat, 70/30+Water Wetter, and dual 12" FALs switched on permanently through two relays. Temperature is measured with a Techtom MDM100.

Activity/Temps @ day/Temps @ nightidling temp./~181-183/~175-178city driving/~185-195/~180-183hw driving/~192-197/~175-185long uphill/~203-212/~195-205

Needless to say, I avoid long hillclimbs during the day...