5.9 electric fan conversion
 

I'm thinking of replacing the stock radiator clutch fan with an electric fan. I live in Las Vegas and the stock clutch fan doesnt seem it can keep up in the summer. Anyone know if there is a kit available? I've had the van for 2 summers and it's acting like my old 99 Durango used to. I dumped a bunch of money into the Durango with new radiator, fan clutch, thermostat, etc and nothing helped. Wondering if there is an electric cooling fan that has enough CFM's compared to the stock fan.

I performed this mod on another car, and now I also own a 5.9L van.

Before you start this project, what is the stock fan not doing? Does the van overheat in the summer?

On the other car ('96 BMW 328is), there was no "kit". You do it yourself.
You'll need
- electric fan
- switched ignition power
- direct battery power, with a relay connecting the switched ignition power, and sufficient gauge wiring to handle the fan electric load
- coolant temperature switch

This last switch...I don't know enough about the van, but the BMW already had this switch for air conditioning purposes.
You may need to get a wiring diagram, to see if this switch already exists.

So, the relay gets power when you turn on the ignition, and when the coolant temp reaches a certain value. When these two conditions are met, it sends power to the fan, directly from the battery (with an in-line fuse).

If you feel real ambitious, you may want to duplicate the BMW system.
They have two fans: one in front of the air conditioning heat exchanger, and the second one is the typical one behind the radiator.
The front one goes on when either the coolant has reached a certain temp (coolant temp switch), or you turn on the air conditioning.

Another design problem here is you don't know the CFM of the stock fan. Maybe just buy the most CFM within a size limitation?

Potential problems
- electrical spike...the BMW has a considerable electrical spike when the fan turns on, but then the electrical system stabilizes within 2 seconds. I don't know how the van will react, but most cars have electric fans, so probably a mute point.
- Installation...I was able to install the fan outside the car first, then drop it in. I just replaced the radiator in the van, and I doubt you will be able to do that. It is also hard to check for interferences when choosing a fan. Measure twice, buy once.

From my van radiator project, I have an extra aluminum radiator that is in like-new condition. You may need adapter fittings for the transmission cooling lines. This may be all you need, but sounds like you've been down that road with the Durango. I will sell it to you for $25, plus shipping from San Douiego to Vegas. Just private message me if interested.

Hope this helps,

Brian

Thanks for the detailed info. Doesn't seem there is enough room to fit a fan in front of the radiator. Just the one in the back. I think my radiator is fine. Just the clutch fan can't keep up in the Vegas heat. I mostly travel in the mountains and desert if the southwest so there is a lot of strain on my cooling. In the summer my engine temp will get pretty high-maybe to the 3/4 mark on the dummy gauge. Same happens when I climb any grade. Had the exact same problem on the Durango. I'm pretty sure I want to go with the electric cooling fan option if I can get it to fit properly.

I meant in front of the A/C condenser. Fans come in different sizes, and you would get cooler A/C for the Vegas heat.

Do you have the stock radiator? If so, I think (but not sure) that this is made of a steel core. See attached. An aluminum radiator (at 125 deg C) will conduct 5 times the heat when compared with a steel core.

i did this conversion on my '94. I used a '96 t-bird electric fan, it covers it pretty well but not completely. Better than some aftermarket fans (I tried a couple). I installed a relay kit/sensor that I connected to an in-line radiator adaptor. I installed this a few years ago when I converted my trans from a 3 speed to Overdrive unit.

The only problem I have had is since the hose adapter is so fat, it doesn't fit in the upper hose (suggested location) I have to use the lower hose and because of that I had to use a lower temp sensor. One nice thing is when I am stopped and the a/c is on the fan is always blowing (sucking) and keeps the air cooler while stopped :icon_cool:

LedZep just so you know, most automotive radiators are constructed of copper and brass not steel. There are steel radiators but they are generally used on heavy equipment. You are correct about the heat dissipation being greater with an aluminum radiator than with the copper/brass radiator. For years when I worked in the HVAC industry I tried to explain to many old school customers that aluminum beats copper hands down. A 1 inch single or double tubed core in aluminum will dissipate as much heat as a 4 row copper core. I noticed that There was no mention of cleaning the AC condenser. I don't know what the insect population is like in the desert but I do know that AC condensers have a fin count of generally 14 to 20 fins per inch which tends to plug up fairly quickly.

Actually most radiators are now made from aluminum, which surprisingly dissipates heat at a faster rate than copper or brass.

Sorry Alloro I didn't phrase that right. What I meant is that generally radiators are made out of copper and brass. The fins can be steel or copper. In today's vehicles aluminum is used predominately.