Two cooling fans (was: 165 question)

[Andrew W. Macfadyen]

Some manufacturers use this system I know  the UK  Rover use it in the higher
performance turbo and V6 models in the 800 range. If you want to take the
electronic route  you could do it several ways using a temperature sensor  (such
as  a thermistor or LM335 sensor) connected to a simple voltage comparator (you
would also need some kind of timer bassed on 555 chip)   or  a better one chip
solution in the form of the Analog Devices  TMP12FP chip  which is designed for
use in Pentium PC and actually  measures airflow and temperature.

Andy MacFadyen

AL8001 at aol.com wrote:

> In a message someone wrote:
>
> >>Wanted to have two fans in pu that came on at
> >>>different temps. Have some minor drivabilty problems in really hot weather
> >>>- hope to have ecm do controlling of fans instead of wiring to have come
> >>>with eng running.
> >>>
>
> It dosn't have to that complicated (searching for a ecm output and table ).
> Look in a auto parts catalog for a water temp switch used for a hot light.
> Many have a small screw covered by paint or sealer. Most of the older Ford
> sensors have a threaded stud with a flat on one side.
>
> Clean off the paint, then turn the screw two turns clockwise. Most engines
> have extra pluged holes in the intake or cylinder heads. Connect the switch to
> the relay for the second fan.  Run the engine and adjust the screw to the temp
> you desire.
>
> Simple, easy and cheap.