Controlling dual fans seperately
Thread Starter
Race Director
Joined: Feb 2006
Posts: 12,239
Likes: 19
From: Chino CA
Controlling dual fans seperately
I have a Dewitt's rad and dual electric fans.....
Both fans come on and off together...but I would like only one to come on and only if needed - the other come on with it...
What's the best (and easiest ????) way to go about this ?
Both fans come on and off together...but I would like only one to come on and only if needed - the other come on with it...
What's the best (and easiest ????) way to go about this ?
Thread Starter
Race Director
Joined: Feb 2006
Posts: 12,239
Likes: 19
From: Chino CA
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,172
From: Hermosa
Yes there are electronic controllers available. I'm not sure what they are but a search for electric fans would give you some good ideas as lots of people have done many different kinds of installs with electric fans.
Melting Slicks
Joined: Dec 2008
Posts: 2,070
Likes: 5
From: N.Richland Hills Texas
We seperated mine... So if one relay ect fails there will still be some cooling... BUT,they still get the signal from one source ..And one comes on now with the A/C selected... Which I've never done,tops are never on...
Burning Brakes
Joined: Oct 2010
Posts: 1,192
Likes: 7
From: Wentzville MO
Racer
Joined: Jun 2009
Posts: 393
Likes: 3
If you are going to use another relay and sender, I would see if you could buy a 1/4 npt switch or you can do what I did and turn down a 3/8 npt sender and rethread, and install in the radiator drain petcock. You will need to ground the radiator to the chassis. I would trust that more then a compression fitting 
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Melting Slicks
Joined: Apr 2010
Posts: 2,796
Likes: 1,197
From: Canberra Australia
2025 C3 of the Year Finalist - Modified
This is exactly what I wanted with mine.
But I wanted to use just the factory sender unit.
Could not find what I wanted so got a friend to build one for me.
(However Dakota Digital do have a fairly good one as well - have not tried it but on paper does a fair amount)
- Press and hold Fan button 1 to set on point for fan 1 and Fan 2 on will be set 10 degree hotter.
- Press fan 1 or 2 to force on either fan. (Manual mode)
- Press and hold Fan 2 button then you can increase or decrease the gap between fan 1 and Fan 2 on points.
-Dual Press 1-2 or 2-1 allows you to then move fan off points up or down for either fan.
Covered on page 20,22 & 30 of my build thread
http://forums.corvetteforum.com/c3-g...1-journey.html
http://forums.corvetteforum.com/c3-g...ourney-20.html
http://forums.corvetteforum.com/c3-g...ourney-22.html
http://forums.corvetteforum.com/c3-g...ourney-30.html
But I wanted to use just the factory sender unit.
Could not find what I wanted so got a friend to build one for me.
(However Dakota Digital do have a fairly good one as well - have not tried it but on paper does a fair amount)
- Press and hold Fan button 1 to set on point for fan 1 and Fan 2 on will be set 10 degree hotter.
- Press fan 1 or 2 to force on either fan. (Manual mode)
- Press and hold Fan 2 button then you can increase or decrease the gap between fan 1 and Fan 2 on points.
-Dual Press 1-2 or 2-1 allows you to then move fan off points up or down for either fan.
Covered on page 20,22 & 30 of my build thread
http://forums.corvetteforum.com/c3-g...1-journey.html
http://forums.corvetteforum.com/c3-g...ourney-20.html
http://forums.corvetteforum.com/c3-g...ourney-22.html
http://forums.corvetteforum.com/c3-g...ourney-30.html
Former Vendor
Joined: Jan 2000
Posts: 5,593
Likes: 631
From: Brighton
All you have to do is put a cut off switch in one of the switch sensor (gray) wires. That way it's automatic with one or two. Since this a ground wire, you don't need a big amp rated device. A small toggle switch will do the job
Thread Starter
Race Director
Joined: Feb 2006
Posts: 12,239
Likes: 19
From: Chino CA
P.S. it's a DeWitts....setup.....!