Wiring Up Thermo Fans

[NZM.031]

hey guys

just need some help wiring up some el falcon fans i got recently, as my clutch fan shat itself. at the moment, its unfused, just straight battery voltage from a switch inside the cabin.. so i wanna get it sorted asap.

im thinking of wiring one to be the primary fan, and the other to come on when the original a/c fan comes on (may even remove a/c fan and just have the 2 radiator fans)

for the primary, i was thinking of having wiring it through a resistor switch, just like the interior fan.. so i can have different speeds (as on full speed one fan really loads up the alternator, let alone two running full speed), the other option, is to have a variable resistor, like the one for the instrument lights, and just wind it up and down... that might be a better idea actually

so it would be always on when the car is running, on speed 1, then i could have a rotary switch wired to a resistor pack, or variable resistor and just wind it up on a hot day, in traffic or after some sort of track work.

would that work?? in thought it will.. and then when the a/c is on, or the temps get to high the other fan will kick in like the original a/c fan would.. spose ill just put a resistor in to slow that one down aswell.

will the load put on the alternator decrease with resistors?? or is it just the voltage thats slowed down... current remains the same??

i love wiring things up and doing a nice neat job... but i could never get my head around electronics.

cheers

Linton

[grigor]

Use a series/parallel circuit to get 2-speed fans.

[blind_elk]

Having a thermo fan running permanently basically defeats the purpose of having a thermo fan. Instead of the normal fan placing load on the engine, the alternator is now placing load on the engine, as it tries to produce sufficient current to drive the thermo fan.

The only time you need the thermo fan running is when the engine gets above some arbitrary temperature setting (can be as much as 10 deg C above normal operating temp). Ordinarily, movement of the car provides sufficient airflow through the radiator to control the engine's operating temperature to the thermostatted temperature.

[NZM.031]

im gonna remove the fans and go back to a clutch fan, its just too much for the little alternator and i dont feel comfortable with it... all the big power and track gtrs etc i see still run a clutch fan, so im just gonna get another one.. ive got a new thermostat coming and some redline water wetter to go in so that should make it better..

cheers guys.