Electric Fan Q&As

Hi,
Im thinking of getting an electric fan for my 72 Duster w/ 360 and need advice.What size of fan should I get(12 inch,14 inch,16 inch?)and what CFM?Also,how do I wire it?Is there a way I can wire it without a temp switch,but just use a relay and a toggle switch?Do I need to do anything to my electrical system since they do seem to have a big amperage draw?thanks everyone:cheers:

Unfortunately E-fans are by no means an exact science on our cars.

I have been dealing with these for some time on my 360 Dart and only recently found a satisfactory solution.

Neither a single 16" or dual 12" fan setup worked for me. I ended up using a fan setup from a Mercedes C-class. It fits over the factory 26" perfectly. I just clipped off the factory mount clips from the E-fan, and drilled holes to line up with the shroud mounts on the Mopar radiator. Then I used some threaded clips to screw in to and it was on. It cycles and cools fine on a 90+ degree day here in North Texas.

Regardless of what fan you use, you will require a relay to power it. The catch here is that any fan powerful enough to cool your engine is going to require a lot of power. During spin-up, the fan draw increases from 0 to 50 amps. Once it hits max RPMs it settles in at 39 amps. Factory externally regulated alternators come in 40 and 60 amp versions, and can be gotten (or rebuilt) in to 100 amp units. Regardless of the rating, they make very little power at idle. Only 10-15 amps typically. The problem is, idle is where you NEED the power to feed your electric fan. Because of this, when the Benz fan powers up it actually discharged my battery. To resolve this I installed a Powermaster 140amp 1-wire alternator. These units put out much greater current at idle than stock, and the voltage is constant across the RPM range. No more dimming lights at idle!

The Benz fan has a built in relay, so I was able to wire directly to battery power and just trigger the relay with a temp switch. If your fan does not have a built in relay you will need to get one. Some manufacturers offer fan controllers that will allow temp switch inputs as well as pressure switch inputs if you have air conditioning. Just remember the relay needs to be large enough to feed the fan at max current draw.

Here is the fan on the car, (still with the factory alternator) followed by a video of the fan when tested.

After all that, I ultimately removed the E-fan and am going back to a mechanical viscous fan. The power draw for a proper E-fan was crazy, and the viscous works just as well, with very little loss in HP. Ultimately I want my car to be reliable, and adding electrical stuff to the car isn't always the way to do it. It may go back on later, but not right now.

I'm having issues myself with a 16" electric fan..... going to try the mechanical (viscous) fan next. Just wanted to put my $.02 worth.

1BadDodge71 said:

Hi,
Im thinking of getting an electric fan for my 72 Duster w/ 360 and need advice.What size of fan should I get(12 inch,14 inch,16 inch?)and what CFM?Also,how do I wire it?Is there a way I can wire it without a temp switch,but just use a relay and a toggle switch?Do I need to do anything to my electrical system since they do seem to have a big amperage draw?thanks everyone:cheers:

Click to expand...

I've been running a Flex-A-Lite Dual Fan system on my Big Block 383 Dart Daily Driver since 2005. Works great.



I used a DERALE Temp Probe / Relay Kit. Install was very easy and quick (less than one hour) . No Upgrade to my electrical system was necessary.

http://chucker54.stores.yahoo.net/elfanwikit.html

I just put a set on my 318. I originally had the setup in my 71 Corvette, but the slanted radiator they use was causing me some issues with airflow at speed I think. The set is a Summit generic set, http://www.summitracing.com/parts/SUM-G4852/. I was even lucky enough that they literally slid into place. They pressure fit between the upper and lower radiator end caps so I don't even need bolts to hold them in. The engine setup is not original and the radiator looks pretty dang thick for a little 318 (probably 2" thick), but the fans work pretty good. When both are one it will bring the temps down nice and low. For now I just have a toggle switch that flips a relay to turn them both on, but I'm putting a temp switch in now that I know they will cool. I bought a thermostat housing spacer that has two 3/8 threaded ports that I was going to put a switch in one.

superdart said:

Unfortunately E-fans are by no means an exact science on our cars.

I have been dealing with these for some time on my 360 Dart and only recently found a satisfactory solution.

Neither a single 16" or dual 12" fan setup worked for me. I ended up using a fan setup from a Mercedes C-class. It fits over the factory 26" perfectly. I just clipped off the factory mount clips from the E-fan, and drilled holes to line up with the shroud mounts on the Mopar radiator. Then I used some threaded clips to screw in to and it was on. It cycles and cools fine on a 90+ degree day here in North Texas.

Regardless of what fan you use, you will require a relay to power it. The catch here is that any fan powerful enough to cool your engine is going to require a lot of power. During spin-up, the fan draw increases from 0 to 50 amps. Once it hits max RPMs it settles in at 39 amps. Factory externally regulated alternators come in 40 and 60 amp versions, and can be gotten (or rebuilt) in to 100 amp units. Regardless of the rating, they make very little power at idle. Only 10-15 amps typically. The problem is, idle is where you NEED the power to feed your electric fan. Because of this, when the Benz fan powers up it actually discharged my battery. To resolve this I installed a Powermaster 140amp 1-wire alternator. These units put out much greater current at idle than stock, and the voltage is constant across the RPM range. No more dimming lights at idle!

The Benz fan has a built in relay, so I was able to wire directly to battery power and just trigger the relay with a temp switch. If your fan does not have a built in relay you will need to get one. Some manufacturers offer fan controllers that will allow temp switch inputs as well as pressure switch inputs if you have air conditioning. Just remember the relay needs to be large enough to feed the fan at max current draw.

Here is the fan on the car, (still with the factory alternator) followed by a video of the fan when tested.

After all that, I ultimately removed the E-fan and am going back to a mechanical viscous fan. The power draw for a proper E-fan was crazy, and the viscous works just as well, with very little loss in HP. Ultimately I want my car to be reliable, and adding electrical stuff to the car isn't always the way to do it. It may go back on later, but not right now.

Click to expand...

hey superdart wat year mercedes did that fan come from??

12 volt 305mm (12 inch) suction fan. Straight blade. Low profile fan - overall depth 52 mm. Approx. weight 1.1 kg.

Long Life motor (also available in LL & VLL versions).

IP68 protected motor - sealed against water/dust.

Airflow 1470 m3/hour at 0 mm water static pressure - Current draw 6.9 Amps.

this what im using.........very skinny,verrrry efficent and note the current draw.

I have a 16in spal the 2400 cfm. I think they have a 2300 and a 3000 also. I use it with the painless temp control set up on 185 off 170. I dont use a thermostat and I have the pump bypass blocked. This keeps my 14-1 comp smallblock cool all day even at an idle .Its draws 25 amp so make sure your alt is good. I used to run the square 60 amp it was ok but on the new motor i uped to the 90amp denso what a diff. I also use a 27x19 alum rad and a modified 8 blade pump. Cools even with march pulleys. I used to have the 2300 straight blade but this one is quieter plus it has renforcements struts between blades. I have also used the mrgaskets fans and zirgo fans and the spal fan is where its at.

What do you guys think of this setup?

[ame="http://www.amazon.com/PROCOMP-ELECTRIC-DERALE-THERMOSTAT-16739/dp/B003R2ZYF4/ref=sr_1_7?s=automotive&ie=UTF8&qid=1290532873&sr=1-7"]Amazon.com: PROCOMP DUAL 12" INCH ELECTRIC FAN W/ DERALE THERMOSTAT KIT 16739: Automotive@@AMEPARAM@@http://ecx.images-amazon.com/images/I/51HjaLtiUbL.@@AMEPARAM@@51HjaLtiUbL[/ame]

I'm currently using a Taurus fan but it looks cobbled together and when I put in my aluminum radiator I want it to look as good as is functions...and for $75 after shipping, it's in my price range...