Electric Fan Q&As
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.
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.
