Electric fan horror stories or successes

[techno1154]

Oh my! XJRubicon,...that is a long list but I agree with all of it. However, keep in mind that a good 90% or more new vehicles sold today have electric fans only and even more electrical gadgets than our XJs. Yes, they sure do have a higher output alternator than the standard unit that come with the XJ. But still,...no mechanical fan, only electric fan/s. They are mostly front wheel drive vehicles. Try to put a mechanical fan on a cross mounted engine. The early British Mini cars from the 1960's had mechanical fans working in reverse. i.e. pulling air from the engine bay and blowing it out some backward facing vents cut into the side over the front fender.

After converting to electric fans on my XJ, the very next thing I did,... yes, the very next day was to replace the alternator with one from a Dakota rated at 160 AMPs. Why? When the fans turn on the lights went low, the radio lost its ability to speak audibly the wipers were reduced to slow motion and worst of all the cooling fans themselves slowed to ..... well it is impossible for me say how slow but that exasperating the very problem I was trying to resolve or should I say add other problems.

I now have a 200 AMP alternator. Still, I would like to add some kind of electrical unit to have one of the fans start up slow and spin up gradually. By-the-way, each fan run independently. One fan keep the heat from the 4.0L at acceptable level, I think as good as the mechanical fan did ( I think :eyes The other fan run only when the AC is on. At that time one fan run constantly while the other cycles with the AC compressor same as the OEM e-fan did. That one would also run when the PCM senses an over heating condition. In addition, the oil from the AW4 is removed from the radiator and plumbed into its own after market cooler.

 

[bluejeepkid]

I once had dual efans. A stock unit and some brand that supposedly pulled around 2000cfm. I now have my stock mech fan and stock efan back in. One thing I am going to do is wire my efan to an aftermarket thermal switch so it will turn on around 190 instead of 212 or whatever the normal temp it comes in at.

 

[bluejeepkid]

Gotta battle with 120 degree wheele trips with the ac on. Lol

 

[XJRubicon]

Oh my! XJRubicon,...that is a long list but I agree with all of it. However, keep in mind that a good 90% or more new vehicles sold today have electric fans only and even more electrical gadgets than our XJs. Yes, they sure do have a higher output alternator than the standard unit that come with the XJ. But still,...no mechanical fan, only electric fan/s. They are mostly front wheel drive vehicles. Try to put a mechanical fan on a cross mounted engine. The early British Mini cars from the 1960's had mechanical fans working in reverse. i.e. pulling air from the engine bay and blowing it out some backward facing vents cut into the side over the front fender.

After converting to electric fans on my XJ, the very next thing I did,... yes, the very next day was to replace the alternator with one from a Dakota rated at 160 AMPs. Why? When the fans turn on the lights went low, the radio lost its ability to speak audibly the wipers were reduced to slow motion and worst of all the cooling fans themselves slowed to ..... well it is impossible for me say how slow but that exasperating the very problem I was trying to resolve or should I say add other problems.

I now have a 200 AMP alternator. Still, I would like to add some kind of electrical unit to have one of the fans start up slow and spin up gradually. By-the-way, each fan run independently. One fan keep the heat from the 4.0L at acceptable level, I think as good as the mechanical fan did ( I think :eyes The other fan run only when the AC is on. At that time one fan run constantly while the other cycles with the AC compressor same as the OEM e-fan did. That one would also run when the PCM senses an over heating condition. In addition, the oil from the AW4 is removed from the radiator and plumbed into its own after market cooler.

Just a couple of things to remember.

Side mounted engines have to be cooled with electric fans, but their cooling systems are designed bigger to be able to handle more heat over more time. A 4.0L is a fairly big engine compaired to most. Its radiator in an XJ is minimal at best just as the brakes are undersized on the XJ. Anyone who has pushed an XJ to its limit with a lift and bigger tires knows!

Another thing to remember, getting a larger amp alternator is not the way to deal with low voltage at idle. The idea is more amps the betteright? Not exactly.
Not all alternators are created equall. Sure the 160 and the 200 can output more amps, but the rating is at a lot higher rpm than idle. I had a custom 160 amp built for my 87' XJ after I put the winch on it thinking it only made sense.
Sure the alt worked awesome while winching, but at idle with the heat and headlights on, they would dim. The reason being the large amp alternators actually put out less amperge at low rpm. Think of it kind of like a gearing issue. The large alternator outputs more but only at a high RPM. It really neds the speed to output.

Best way to deal with the electrical stress of electrical fans at idle is to get a smaller pulley on the stock alternator. This will spin the alt faster and produce more amps at idle. Now you can do the same with a high amp alt but you are not going to get the amps you could from a stock unit at idle.
Lifespan of the alt is effected by the smaller pully because its spinning faster but not by enough to worry about. Sure, you could get a high amp alt to spin fast enought to not dim the lights with everything on, but it would mean that the crank pully (input power and speed into the belt system) would need to be larger because you can only go so small with an alt pully. Another thing to consider when redesigning the electrical system is the smaller pully has less contact area on the belt so it will also wear the belt more. The possability of the belt slipping on the pulley in increased.

...thats all I got ta say about dat!

As for the AW4 all trannys like to be at operating temp. Running them with their own stand alone cooler will eliminate them from being warmed by the engine in winter. A cold tranny is not going to blow up like an over heated tranny, but its still not good for an automatic to be cold. Everything is designed to a tolerance that is at operating temp. So while eliminating the trannys heat from the engine may be good, the tranny will suffer with out the engines heat in winter. For this reason, I almost think that an aux tranny cooler should be installed behind the radiator so that it can be warmed by the engine again without contributing to the engines thermal demand on the radiator.

That being said, the 98' I just picked up has the aux cooler behind the grill and no connection to the radiator.
Its ok for this summer but I will probably try to get a new radiator for the use of the onboard tranny cooler before winter.

XJR

 

[techno1154]

XJRubicon, your post and most on this thread have more good responses than one can shake a stick at. I will comment on 2 of them.

1) Alternator... The alternator I am using now was built bigger overall
and produced more AMP at idle than the OEM unit. The 1996 OEM
alternator was rated at 90 AMP. Try 2-50 AMP (at startup) fans and all
the other OEM electrical units. I also replaced the pulley with a smaller
one from Summit Racing.

2) AW4 cooling. I live in Florida. It do not get very cold here. This winter here
in Jacksonville there were only 3 nights where it got as low as 29
degrees then to the mid 40's in the daytime. Also, I have the ability to
cover the cooler if I need to raise the temperature. Overcooling is not a
concern here in Florida.

I thank all who contributed to this thread. I am certain it is helpful to the OP.

 

[Miller88]

I switched back to the XJ fan clutch (brand new one) from the ZJ fan clutch. Will be interesting to see how it works this summer on wheeling trips. The ZJ fan clutch was nice because it would move massive amounts of air when going back and fourth in mud.

However, I do run a hood shim when wheeling.

My Focus has an e-fan, obviously, being a FWD car. I can't even get the single electric fan to come on unless it's over 100 degrees and I have the AC on. The radiator is larger than that of my XJ. It has a larger engine bay, half of the engine displacement, and no cat converters under the hood.

 

[jeeperjohn]

I have been through just about every fan setup out there and I can say with certainty the stock engine driven setup is best when functioning properly. The main reason I went electric is I can't stand the noise of the mechanical fan. You can get good cooling with electric fans but it is very expensive and requires significant modification. If you have the money and want to do electric fans use SPAL fans. There is no other fan (with the possible exception of a few OE fans like the Taurus one) which moves as much air and is as reliable. I have had many overheats due to fans made in China. They simply don't last. If top notch cooling is what you need stick with the stock setup.

 

[cal]

I'm sitting here now looking at the SPAL catolog trying to figure out if its worth $150 to experiment with electric again..

but man, 45 amps for a fan...

 

[srmitchell]

For a while, I had a dual factory 97+ e fan set up on mine. The install was clean and I was very proud of it.


I used a hayden fan controller from oreilly- it used a little probe that sat inside the radiator fins.
On paper, it was a good idea, but the amp draw was high, and the fan controller kept failing. It had a lifetime warranty, but it was a pain to keep removing.

The temps constantly went above 210, and I had to hardwire both fans to preemptively cool the engine. Since there was no auto-control anymore, I would not let anyone drive my jeep because I was horrified that they would forget to run the fans!

I was about to install my winch too, and I had this vision of trying to winch with two efans running on a hot sierra trail at altitude. No thanks.

I now run a Hayden HD clutch from oreilly's, and the one stock e fan. I do have the fan on a switch so I can operate it early if needed. I like this setup way more and temps stay normal, even while winching.

Here's my switch setup- top is for aux lights and the bottom is the efan.

 

[cal]

you didnt just put the fans on a relay that comes on with ignition?

 

[techno1154]

I'm sitting here now looking at the SPAL catolog trying to figure out if its worth $150 to experiment with electric again..

but man, 45 amps for a fan...

This is what I went with from day one. Expensive, noisy, power hungry and required a lot of massaging to get them to fit.

http://www.summitracing.com/parts/der-16928/overview/

As said before, one fan is usually enough to keep temperatures in check in the South Florida summer. With the AC running both fans run and the temps stay about 200 degrees.

Do not cheap out on cooling fans for the 4.0L. You will save yourself plenty of frustration later on. I remember in the early days prior to 2004 many forum user turned to e-fans to cure an over heating problem. No fan that would fit under the hood of an XJ could fix a bad cooling system.

 

[cal]

thats funny

i looked at those fans and thought it would be cheaping out

 

[jeeperjohn]

I'm sitting here now looking at the SPAL catolog trying to figure out if its worth $150 to experiment with electric again..

but man, 45 amps for a fan...

I felt the same way until I installed two 10" spal fans. After using them I am well satisfied with them.

 

[cal]

... yeah.. i wouldn't run a 10" fan on my steering cooler

 

[MoparManiac]

I have two 12" SPAL fans on my 31x19 Griffin. They move a shitload of air and have kept my 440 cool during a few races, one when it was 95 degrees out.

I think people tend to cheap out on electric fans and expect the world of them.

 

[cal]

I was looking at 12's as well. We'll see, I'm feeling pretty broke right now and may keep the mechanical stuff.

 

[northwestxj]

I have my winch located behind my front crossmember so I can't fit a mechanical fan anymore. I run two 97+ electric fans and my rig has never overheated since I changed about 3-4 years ago. It only gets hot on long grades going up forest roads, but it has always done that. I have one fan running off a SPAL fan controller and the other one is on a switch. I only need to turn on the second one once in a while driving around town and during the summer wheeling.

 

[O-Gauge Steamer]

Before I replaced all of the mechanical components in my cooling system (fan and pump...) a brand new 200A Alternator was installed along with a fuse. The stock fusible link was eliminated at the same time. I saw no sense in asking more of the stock Alternator than it was prepared to deliver.

The first pass at it, I installed a two speed Ford Taurus fan in place of the Jeep mechanical fan and I installed it in the factory fan shroud. In order to get the clearance needed for the electric motor, the centering pin of the fan drive had to be trimmed, very nearly flush, back to the pulley. I also installed button head bolts to gain some clearance.

I ran this setup for about two years and that version was replaced with the Flex-a-lite system consisting of their aluminium radiator and the accompanying three electric fans.

For control of the fans, the original setup had the Ford running on low speed with the ignition. A full time fan. When the PCM called for electric fan the Ford would shift over to high speed and the Jeep fan would, of course, run as well. Another layer of control was installed with the electric water pump. I use a Davies-Craig EWP115 pump and controller. The controller is set to control the ECT in 5ºC degree increments with a range of 75ºC to 98ºC degrees. By default, the controller requests fan at 3ºC degrees above the user defined setpoint.

This worked OK. Not great but OK.

Not being overly happy with it being OK, the CSF radiator was replaced with the Flex-a-lite aluminium unit. What I did not use was the fan controller that came with the new radiator. Instead, the existing control was slightly modified to run the additional fan.

The control setup now has the passenger side fan running with the ignition and the other two fans power up by command of either the PCM or the DC controller. Both controllers, the PCM and the DC, operate relays that send battery voltage via dedicated fusing to the respective fans.

I have been asked why I run one fan full time, the answer is that I value my Alternator. Jeep has the Alternator receiving air flow full time and I feel that that is a good enough reason for me to replicate that portion of the stock installation.

With a setpoint of 90ºC degrees the Jeep, for the most part, operates within a range of -0/+4ºC of that setpoint.

Another reason I installed the DC EWP115 is that the pump runs for two minutes after the engine is shut down. Even without the fans operating, the engine cools down remarkably. It is normal for an engine to temperature spike after shut down and, should the DC ECT sensor see it, the fans will kick on for less than a minute to aid the post run cool down. This completely eliminates vapour lock after shutdown.

All things considered, I would do this again of the need was there.

For reference: 90ºC = 194.00ºF

There is, actually, another benefit to using an electric water pump. The engine comes up to operating temperature quicker than it did with the stock components installed.

The reason is simple. The EWP115 is a PWM (Pulse Width Modulated) system. This means that the motor has infinitely variable speed from 0 RPM to it's full rated speed. They do this by a combination of varying the voltage and the amount of time the drive signal is sent to the motor. At start up, the controller send 6VDc to the motor in a 50% duty cycle. This means that the motor is pulsed thus slowing it down to approximately 25% of the rated flow. Just enough flow to prevent hot spots from forming.

The installation is not cheap so, if you are looking for a cheap JY solution, this is not it. If, however, you are looking for a bullet proof system that is dead reliable, this is one way to go.

 

[Redsnake]

I've been running the Dirtbound Triple E-Fan kit for ~ 2 years now. Along w/an Aluminum radiator. Cooling has been just OK. I'd not do it all over again if given the option. My kit did not come w/the Spal fans that ... last I checked... were being offered w/the new kits. Mine are what I assume to be Made in China fans.

The best part about the e-fans are that they stay on for a few minutes after my engine shuts off and it helps w/the vapor-lock issues on my '01 XJ.

I may end up swapping back over to the OE Clutch fan and keep the OE E-fan wired up to stay on when I shut the engine off this Summer. Just depends. I would spend the money elsewhere if I had to do it all over again.

 

[WebDog]

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

Actually we had an issue with the CSF 3 core all brass and the Champion 3 core aluminum radiators, once we switched back to a OEM replacement ($100 Autozone) radiator the jeep ran perfect again.

Since then we have recommended the same fix and have heard others have the same success with a OEM style radiator vs the "3 Core High Performance" radiators...

We since switched to SPAL fans as they are more readily available for us, but I know of over 300 of the old style kits out there without issue.