6V fan control

[DonaldSmith]

Years ago, I installed a 12 volt pusher fan in my DeSoto Suburban, for extra cooling during parades.   Of course, i haven't been in a parade since, but the pusher fan saved the day recently when my fan belt destroyed itself. 

 

I want to delete the belt-driven fan, for various reasons, but need a reliable power source for the pusher fan.  As it is now, I have a second 6-volt battery in series to provide the 12 volts for the pusher fan and for electronics in the cabin.   But the second battery has to be recharged periodically.

 

I can get a 6-volt pusher fan, run off the main battery which is recharged by the alternator, and get a separate power pack for the electronic gadgets.  But I haven't found a thermostatic control that works on 6 volts.  I think part of the problem is that the common relays need 12 volts to work.   

 

Does any one know of a 6-volt fan controller?

 

[Don Coatney]

I would think that with this pictured controller you could use 12 volts to run the control circuit (low amp draw) and 6 volts to run the fan motor (high amp draw).

 

[Plymouthy Adams]

a horn relay of stock era is 6 volt and can be used to control the higher current for turning on the fan..the controller should only be a thermatic switch properly with the senor properly positioned in the radiator fins to detect the desired operating range..that simply is nothing but a set of contacts..the low current of the relay energizing coil should not prove to be to much for this device be it 6 or 12 volts in your car.  While many thermo switches for car fans are block mounted or on the rad using a threaded bung...you can get generic ones...that is only a switch...quick look shows one just for reference to give you an idea of what is out there if you look...lot of fan makers also have similar..most however are packaged all in one with the relay...the relay is your voltage specific device

 

http://www.ebay.com/itm/Switch-Radiator-Fan-Temp-Thermo-Adjustable-24-0100-/191259623253?pt=Motors_Car_Truck_Parts_Accessories&hash=item2c87f63f55&vxp=mtr

Edited July 27, 2014 by Plymouthy Adams

[pflaming]

I saw how came on, so left him to you. lol

[Don Coatney]

Nice thing about the controller I pictured above is it is adjustable down to the comfortable temperature ranges of the flathead 6. Use of the radiator probe only would eliminate the adjustment feature. Weather the adjustment feature on this controller is 6 volt compatible is unknown to me. 

[Plymouthy Adams]

Don..I am thinking that the one I pictured and is listed as adjustable is rated in Celsius  (24-100 degrees)

[DonaldSmith]

Don, I have a Hayden 3647 thermostatic control now, thanks to your photo which you had posted some time ago, and the control works well for my 12 volt fan.  My mission, should I decide to accept it, is to cobble together a 6 volt controller for a 6 volt fan. 

 

... or go some other route.  I could leave things as they are, and be diligent about monitoring and charging the auxiliary battery, or devise a way to charge the battery automatically.   Obviously, the cares of this world are minimal or are beyond my control, so that I am free to obsess on this.   

 

And, as Mr. Phelps on Mission Imbecile was advised just before the weekly assignment tape self-destructed, paraphrased here, "If you or any part of your cockamamie contraption are killed or captured, the Secretary will disavow any knowledge ..." 

[Young Ed]

If the controller requires little power could you run a 6v to 12v invertor and then use that to trigger the 12v controller?

[desoto1939]

I know Scott Fans does make a 6 volt fan and I also think they had the thermostatic control style.  I know these fans are not cheap but instead of going to all the trouble of two batteries this would work and also get a positive ground 6v to 12 negative converter in the car to run your gauges.

 

Just a suggestion

 

Rich Hartung

desoto1939@aol.com

[1941Rick]

As I am not a fan of electric fans, I have to ask why do you want to go that way......what drives your water pump when the belt breaks.

A cooling system in good condition will cool your engine in all conditions. When ever there is enough room for a belt driven fan, go for it.

I went the electric route on my 41 and it did squat, but impede the free flow of air. Put in a good radiator and all overheating went away. ( along with the electric fan).

Recently went on a cruise up to a ski hill....14 cars left the bottom of the hill. 3 miles 12% and 7 that varied around 6%. At the top if the hill there were only 10 cars. All 4 that did not make it , over heated , had electric fans.

[nonstop]

I would likely have to agree with 1941Rick. Not a fan of el centric fans either. I have put them in plenty of cars, but was always nervous. I would think a 6 blade fan and aluminum radiator would be more effective, simpler, and possibly cheaper.

Was it an original fan or flex fan that destroyed itself? If flex fan, there is your problem right there!

If you are firm going with the electric fans, I don't see why you couldn't just use the adjustable controller and probe above to control a relay to run the 6 volts to the fan.

[Don Coatney]

......what drives your water pump when the belt breaks.

 

Nothing drives the water pump nor the fan when the belt brakes

 

 

. Put in a good radiator and all overheating went away. ( along with the electric fan).

 

What did the most good? The new radiator or the original cooling fan?

 

I have been using an electric fan only for 10 or so years. I started to have some cooling issues and my radiator was leaking so I replaced it with a new aluminum radiator but kept the electric fan only. My engine now runs cooler due to the increased heat transfer and efficency of the new radiator. I am happy with my electric fan.

[Adam H P15 D30]

This is why I went electric. A lot less damage if they fail. Newer cars have been using them for years.

[Plymouthy Adams]

I have a couple cars here that have electric ans from the factory and cooling big 440 engine..now these cars are 40 years old and while the fans are still working I do not feel they are near as efficient and powerful in CFM as todays new designs and will be upgrading these..I say this for the guys looking to retrofit...get the newer units if possible..

[wagoneer]

Bringing this old thread on an excellent topic up to date -- I'm curious to hear how folks are addressing electric fans today. 

 

I found this simple setup from speedway motors.

 

I'm thinking a large 16" pusher fan mounted in that wide open space in front of the radiator is perfect.

https://www.speedwaymotors.com/Speedway-6-Volt-Electric-Cooling-Fan,56152.html?sku=910151-16

 

A 6 volt relay

 https://www.speedwaymotors.com/6-Volt-Electric-Fan-Relay,66474.html

 

Ideally would like it to be automatic or variably controllable so it's silent. They have a pro kit that includes a sensor.

 

https://www.speedwaymotors.com/Electric-Fan-Relay-Wiring-Kit-Pro-Series,293932.html

 

And provide some handy wiring diagrams.

 

Now... only question is whether the temperature sensor would send enough resistance to register properly on/off to the 6volt relay, and whether this system cares

whether it's positive or negative ground.

 

[Sniper]

The sensor, in this drawing, is typically an on/off switch that supplies a ground when on, it cares not about voltage.

 

I'd be more concerned about the fan CFM, which I don't see listed.  But looking at the amp draw, 6 to 10, it's going to be very low.

 

Modern cars with electric fans and good cfm ratings tend to draw closer to 30A at 12v, the 6v equivalent would be closer to 60A.