So I keep finding people talking about the cfm of the electric fan setups from the ff dynamics and the dirtbound setups but I don't see a lot if reviews. For those of you who have them do you see mpg gains, do you have cooking problems? Tell me your personal experiences.
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Electric fan horror stories or successes
- Thread starter smiley
- Start date
souske
NAXJA Forum User
- Location
- The land of competition
do a search for overheating, then see how many developed after folks installed electric fans
- Location
- Hammertown, USA
didnt dirtbounds shop jeep get so hot with electric fans that the fans soften and damaged the radiator?
thats about my experience with electric fans too
thats about my experience with electric fans too
yossarian19
NAXJA Forum User
- Location
- Grass Valley, CA
You *can* switch to electric fans successfully. Depending on your climate & intended usage, this may work just fine.
With the exception of a Ford Motor Company electric, used in Volvos and Lincolns and Taurus', they don't move as much air as a mechanical.
My personal experience with an electric was a 14" 2100 CFM unit. I first wired it to come on with the AC fan (when the computer sees a hot engine or an AC request). I didn't overheat but this wasn't a good setup. Engine chronically was bouncing off the 220 mark, where the fans came on and cooled it, until it bounced back. No power or MPG difference observed.
I then wired it to be on whenever the ignition was on. Only in reeally slow driving would the AC fan / factory aux fan come on. If I'd gained any power / mpg before, I was gaining less so now.
With that setup and a probably-too-heavy trailer, the Jeep was overheating at 35 mph up hills. Years before, I had a ~12 foot camper packed with my worldly possessions and I towed it up / down the Rockies without over heating. That was with the mechanical fan. Granted, different trailers and different hills. It was still good enough evidence for me to go back to the mechanical fan.
Even my original (I think. It's at least 80K old) fan clutch out-cools 2100 CFM fan.
As for the DBO triple fan setup... I think they tested it and admitted that the factory setup pulls more air.
A volvo / ford electric fan, if you keep the original auxillary fan in place too, will out flow a mechanical "I'd think", definitely at idle and probably up through 30 mph (when cooling fans generally become ineffective as the wind across the grill takes over).
If you want simple, cheap & brutally effective, get a ZJ fan clutch (not the "super" or "severe" duty one) in there.
Or you could make a fan clutch eliminator, but that's getting nutty...
With the exception of a Ford Motor Company electric, used in Volvos and Lincolns and Taurus', they don't move as much air as a mechanical.
My personal experience with an electric was a 14" 2100 CFM unit. I first wired it to come on with the AC fan (when the computer sees a hot engine or an AC request). I didn't overheat but this wasn't a good setup. Engine chronically was bouncing off the 220 mark, where the fans came on and cooled it, until it bounced back. No power or MPG difference observed.
I then wired it to be on whenever the ignition was on. Only in reeally slow driving would the AC fan / factory aux fan come on. If I'd gained any power / mpg before, I was gaining less so now.
With that setup and a probably-too-heavy trailer, the Jeep was overheating at 35 mph up hills. Years before, I had a ~12 foot camper packed with my worldly possessions and I towed it up / down the Rockies without over heating. That was with the mechanical fan. Granted, different trailers and different hills. It was still good enough evidence for me to go back to the mechanical fan.
Even my original (I think. It's at least 80K old) fan clutch out-cools 2100 CFM fan.
As for the DBO triple fan setup... I think they tested it and admitted that the factory setup pulls more air.
A volvo / ford electric fan, if you keep the original auxillary fan in place too, will out flow a mechanical "I'd think", definitely at idle and probably up through 30 mph (when cooling fans generally become ineffective as the wind across the grill takes over).
If you want simple, cheap & brutally effective, get a ZJ fan clutch (not the "super" or "severe" duty one) in there.
Or you could make a fan clutch eliminator, but that's getting nutty...
sidriptide
nobody of any consequence
- Location
- western massachusetts
one problem your going to find on the interweb, is that the only time there is real discussion is when someone is having a problem and they have an E fan for one reason or another.
you will be hard pressed to find a "i swapped to an Efan and my system works great!" kind of thread. success tends to be silent because you move on to something else.
i've had good succes with E fans in hot rods and customs installations, but the XJ seems to be a unique system that in most cases really does work best in stock configuration, (please note that this statement leaves plenty of room for the "mine works great" crowd )
but with a good amount of research and trial and error it certainly can be done, but that much effort/expense needs to be weighed against whether or not you really need to introduce a variable into a system that may already run well, or if you are troubleshooting.
you will be hard pressed to find a "i swapped to an Efan and my system works great!" kind of thread. success tends to be silent because you move on to something else.
i've had good succes with E fans in hot rods and customs installations, but the XJ seems to be a unique system that in most cases really does work best in stock configuration, (please note that this statement leaves plenty of room for the "mine works great" crowd )
but with a good amount of research and trial and error it certainly can be done, but that much effort/expense needs to be weighed against whether or not you really need to introduce a variable into a system that may already run well, or if you are troubleshooting.
Great point, sidriptide. I was hoping some people would come out who had just decided to switch. I am big into PM and I just reached 135,000 on my dd. Runs perfect with my stock setup which has never been changed.... original water pump, thermostat, radiator.
- Location
- Williams AZ
My one small piece of advice for running an electric fan, I found out the hard way. I ran my electric fan using a 30 amp maxi fuse, figured that would be enough. Blew the fuse on the freeway in traffic, car was over 270 degrees and boiling when I got to the side of the road. So my word of advice is this, do not run a fuse. Run a circuit breaker and a high current one at that.
- Location
- In the islands
I do agree with Sid. Most of us who have changed to electric fans without an increase in heating problems simply do not mention it but simply move onto the next issue or modification. My Derale dual fans setup have worked well for me for almost 10 years. They were installed in May of 2004. One is set to come on when the cool side of the radiator reaches 180 degrees. Anyone of the two fans will pull the temperature back down in short order even in the South Florida summer afternoon rush hour traffic. With the AC on and both fans running, the temperature stay below the 210 mark. There is however one problem that I overlooked when I made this change. That is the AW4.
Now that the cool side of the radiator getting hotter than it would have with the mechanical fan the AW4 ran hotter than it used to. This of course caused the engine to get hotter faster in stop and go traffic thus necessitating an external oil cooler which I added years later.
Although I am satisfied with my E-fan setup, I would not do it again given what I now know. As a matter of fact, I am a firm believer that a good quality (OEM) radiator along with an OEM water pump, thermostat and radiator cap is capable of maintaining proper coolant temperature in the 4.0L engine.
WB9YZU
NAXJA Forum User
- Location
- Madison, WI
Good info.
I bought a XJ with AW4 and an efan conversion.
As stated, it does nothing except heat up quicker in the winter (which is kinda nice )
You don't save any gas, because the aerodynamics of an XJ are just flightly better than a brick. And you don't gain any power because the parasitic loss of the fan has been eaten up by the extra load on the alternator. On the trail I end up running the replacement fan all the time just like the regular fan, and if I run the AC on the trail, it tends to heat up with both fans running.
I stay away from nud anyway, however I did see a fellow's fan fail because he got dirty water in it. He was so screwed.
I have the parts to convert mine back, I just need to do it.
-Ron
I bought a XJ with AW4 and an efan conversion.
As stated, it does nothing except heat up quicker in the winter (which is kinda nice
)You don't save any gas, because the aerodynamics of an XJ are just flightly better than a brick. And you don't gain any power because the parasitic loss of the fan has been eaten up by the extra load on the alternator. On the trail I end up running the replacement fan all the time just like the regular fan, and if I run the AC on the trail, it tends to heat up with both fans running.
I stay away from nud anyway, however I did see a fellow's fan fail because he got dirty water in it. He was so screwed.
I have the parts to convert mine back, I just need to do it.
-Ron
XJLI
NAXJA Forum User
- Location
- Long Island, NY
even when the fan clutch is completely worn out the fan still spins. when your fancy pants efans die/blow a fuse/dont pull enough air you are simply SOL. a new fan clutch is 40 bucks and can be changed in half an hour. the mech fan pulls a stupid amount of CFM when the clutch locks up.
KRG.FAB
NAXJA Forum User
- Location
- Jacksonville, FL
Is there a benefit of having a e fan when it comes to water crossing? Ie not spraying the entire engine bay with water?
XJLI
NAXJA Forum User
- Location
- Long Island, NY
the water will slow the fan down quite a bit once you get deep enough. i've heard people say "OMG THE FAN TURNS INTO A PROPELLOR AND EATS YOUR RADIATOR GOBBLE GOBBLE" but i have never once seen or heard of it actually happening. i played submarine with my 93 XJ a whole lot and never had any problems with the stock setup.
Miller88
NAXJA Forum User
- Location
- Syracuse NY
Friend of mine had the dirtbound kit.
When he first got the XJ, it overheated and popped the stock radiator. He replaced the radiator, water pump and installed the DBO triple fan kit while he was in there.
The XJ constantly overheated after that. The fans did work reliably, until he hit a water crossing and water ate the bearings. They were replaced once and same thing happened again.
He went to a ZJ fan clutch and E-Fan setup.
When he first got the XJ, it overheated and popped the stock radiator. He replaced the radiator, water pump and installed the DBO triple fan kit while he was in there.
The XJ constantly overheated after that. The fans did work reliably, until he hit a water crossing and water ate the bearings. They were replaced once and same thing happened again.
He went to a ZJ fan clutch and E-Fan setup.
KRG.FAB
NAXJA Forum User
- Location
- Jacksonville, FL
Good to know. Sounds like I'll save a couple bucks and some headaches and just keep what works.
- Location
- In the islands
Funny! I have done many water and mud crossings and have not had a problem wit either fan or the bearings in them. Here in North Florida I have been in sand/muddy water over the hood and the top of the intake manifold still have tell-tale signs i.e. sand on top of it. Do you/your friend have the fans running all the time? On my XJ, the fans only run when needed to cool the engine down then they shut off automatically. I do not run the AC when wheeling. I open the windows instead.
In my humble opinion, if you have to have the e-fan running all the time then it is better to just have the OEM mechanical fan. You get no benefit whatsoever when the e-fan run constantly over the mechanical fan. At the same time, when the XJ is up to highway speed and I think about 45 MPH the e-fan become almost useless. There is an engineering term known as static air pressure. At a certain MPH, the static air pressure greatly reduces the e-fan's ability to move air engine hot or cold.
Take these observations from a person who have been using dual e-fans for almost 10 years. Hind sight is always20/20. I probably will not go back unless I move to a hilly part of the country or I tow a trailer. I live in Florida which is boringly flat (most places) and almost never have more than about 400 pounds total weight added to the XJ so over heating is not a big issue for me. In addition, I completely service the cooling system every 2 years.
jrowell
NAXJA Forum User
- Location
- Bakersfield
I know this to NOT be the case for my heep. Cruising down the freeway 65mph if it's warm outside the temp will slowly climb to 210. Turn on the E-fan (mine is on a manual switch) and it will immediately brings the temp down to 195.
Electrics fans should only be used if there is no way of using an efficient fan clutch run off the motor.
At 20-30 amps per electric fan at startup and at least 10 amp draw while on... Imagine your alternator trying to output at idle to keep up with it!
Now add headlights, and Heat/ AC on and you add another electric fan into the mix. Not only is it a large load on the alt thats going to be harder on your serpentine belt (tiny pulley compared to stock mechanical fan) but think about the battery constantly going from a discharge state to charging. All them mini cycles are hard on a lead acid battery.
Then take into account that all electrical hates to be undervolted, and you can understand that with every cycle the electrical components are being stressed. Most are used under rated so if there is spikes in the power system they can handle it. But it was never designed to deal with a 60 amp surge from two fans turning on. Think of startup... High ampdraw to operate the starter and then soon as it starts another surge of 30-60 amps on a battery that already was pulled down from starting the truck.
Say you have the headlights on, the defrost going, operating the ac to take the moisture out of the air, creating more heat in front of the radiator, wipers going, two electric fans, the ac fan.... Its easy to understand that that is too much load for an alternator sitting at a stop light with the brake lights lit.
Low voltage causes higher amp draw, higher amp draw causes heat, heat kills electrical.
All of this adds up to the reason these trucks don't come with electric fans from the factory.
In 99' when they needed to meet emissions and lost some HP because of it, did they put an electrical fan in to regain the power? No, they redesigned the entire intake system to produce more power.
Life expectancy of an electric fan goes to shit with one dunk in the mudhole as the factory mechanical fan would just shake it all off!
Also the electric fans themselves produce more heat, not much but it is there, something the mechanical fan does not do.
Just some food for thought!
XJR
At 20-30 amps per electric fan at startup and at least 10 amp draw while on... Imagine your alternator trying to output at idle to keep up with it!
Now add headlights, and Heat/ AC on and you add another electric fan into the mix. Not only is it a large load on the alt thats going to be harder on your serpentine belt (tiny pulley compared to stock mechanical fan) but think about the battery constantly going from a discharge state to charging. All them mini cycles are hard on a lead acid battery.
Then take into account that all electrical hates to be undervolted, and you can understand that with every cycle the electrical components are being stressed. Most are used under rated so if there is spikes in the power system they can handle it. But it was never designed to deal with a 60 amp surge from two fans turning on. Think of startup... High ampdraw to operate the starter and then soon as it starts another surge of 30-60 amps on a battery that already was pulled down from starting the truck.
Say you have the headlights on, the defrost going, operating the ac to take the moisture out of the air, creating more heat in front of the radiator, wipers going, two electric fans, the ac fan.... Its easy to understand that that is too much load for an alternator sitting at a stop light with the brake lights lit.
Low voltage causes higher amp draw, higher amp draw causes heat, heat kills electrical.
All of this adds up to the reason these trucks don't come with electric fans from the factory.
In 99' when they needed to meet emissions and lost some HP because of it, did they put an electrical fan in to regain the power? No, they redesigned the entire intake system to produce more power.
Life expectancy of an electric fan goes to shit with one dunk in the mudhole as the factory mechanical fan would just shake it all off!
Also the electric fans themselves produce more heat, not much but it is there, something the mechanical fan does not do.
Just some food for thought!
XJR
