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Triple efan wiring questions

jdjohnson

NAXJA Forum User
Location
Yuma
So while my motor is getting rebuild i decided to redo the entire cooling system on my 88 4.0. Got the 3 core CSF Rad, dirtbound triple fan shroud, Flowkooler water pump, Hesco hi flow newer style housing with the sensor plug, and all new hoses.

With the back story of all the parts my question is this, is anybody running the triples as 2 normal and 1 ac/hot or is everybody just running all three together on a switch? Also what kits are you running with your setups? I like the OE idea of a mostly AC only fan that aids if temps get over 225 or whatever its set at. Im curious as to hear what everybody else has either tried or has.

Before anybody says it i live in yuma where it is 115+ during the summer so YES AC is staying(after i rebuild all of that too). haha

Also if anybody has good info on 10in efans im in the market.

JD
 
With that kind of heat I'd either run them all all the time (you can't overcool..) or do 2 full time and 1 on a thermal sensor.
 
With that kind of heat I'd either run them all all the time (you can't overcool..) or do 2 full time and 1 on a thermal sensor.


Thanks cal. After a little more research i think i can get away with running 2 different setups, like you stated. An F5 from painless for two of them utilizing the sensor spot in the newer style thermostat housing so i can adjust when they come on, have a switch for cutoff, and the ability for both on. The other setup for the single would be AC on and have another switch for full on or full off. That way i can have all on, all off, or let them do there own thing. The best of all worlds i guess. Makes sense in my mind but lets see if i can put it to paper and then actually to the rig.

I just figured that someone on here is running triples and would have some sort of a different setup other then all on or all off. I would run them all on a switch but i learned from my previous days that im a dummy and sometimes forget to switch them on. oops...
 
Why add a switch? particularly for full off? You're adding a point of failure who's only normal function is to make you overheat. :)

I think what you're failing to realize is that a triple 10" fan setup is barely adequate to cool a 4.0 in normal conditions. If you want to do it, do it, but don't put a bunch of work into complicating it or you'll just make it fail. Run 3 fans. Run them all the time. Run each on its own wiring and relay.
 
With that kind of heat I'd either run them all all the time (you can't overcool..) or do 2 full time and 1 on a thermal sensor.


But you will "pay" for them to run via amp draw = hp draw from the alternator. Not to mention, you'll reduce the service run life of them considerably.

I have a CSF radiator on my 4.0L, live in GA (95*+ degree days) and am without a clutch fan. When cruising down the road, the fans never run - unless A/C is switched on of course. You really only need them to operate at low speeds.

I would recommend adding a higher temp sensor (195* plus) and using that as your coil signal to switch the additional two. Wire the single fan up to the OE connection via a relay and verify if your original temp sensor is a 185*. I hate Chrysler's wiring, so I would again use it as a coil signal for a relay. This way the one comes on above 185 and/or with A/C. The other two will come on at 195 - which should only happen at low speeds. Running them all of the time will tax everything more than you need. Switches aren't necessary.

I sincerely believe the triple fan setup is NOT inadequate. I run only the OE A/C fan right now - that's it. This kicks on at around 220 and turns back off after falling below 195. This is an OE water pump, CSF 2 row, and heater core intact - 5 speed tho.

Another note which may or may not be applicable to you. If you have deleted your heater core, be sure to plug the individual lines rather than loop them. Looping them creates a terrible situation for the OE cooling routing and will quickly cause overheating issues.
 
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I have the dirtbound setup with a sensor. The 2 outer fans come on at 180,and the 3rd at 195. I still need to add a master switch to run them whenever I need/want.
 
But you will "pay" for them to run via amp draw = hp draw from the alternator. Not to mention, you'll reduce the service run life of them considerably.

I have a CSF radiator on my 4.0L, live in GA (95*+ degree days) and am without a clutch fan. When cruising down the road, the fans never run - unless A/C is switched on of course. You really only need them to operate at low speeds.

I would recommend adding a higher temp sensor (195* plus) and using that as your coil signal to switch the additional two. Wire the single fan up to the OE connection via a relay and verify if your original temp sensor is a 185*. I hate Chrysler's wiring, so I would again use it as a coil signal for a relay. This way the one comes on above 185 and/or with A/C. The other two will come on at 195 - which should only happen at low speeds. Running them all of the time will tax everything more than you need. Switches aren't necessary.

I sincerely believe the triple fan setup is NOT inadequate. I run only the OE A/C fan right now - that's it. This kicks on at around 220 and turns back off after falling below 195. This is an OE water pump, CSF 2 row, and heater core intact - 5 speed tho.

Another note which may or may not be applicable to you. If you have deleted your heater core, be sure to plug the individual lines rather than loop them. Looping them creates a terrible situation for the OE cooling routing and will quickly cause overheating issues.


You can sincerely believe that all day long. I have made *extensive* studies of the Cherokee cooling system, tried most combinations, and discussed the triple threat fan system with its designer at some length (he agrees it wouldnt keep my system cool). He was very forthcoming with the information he had, which I do like.

The fact is, my mechanical fan pulls ~4400 CFM at 3000 rpm on an anemometer, which is almost twice the max airflow of the triple threat kit. Thats without adding the electric aux fan that Jeep felt was necessary if you had even just AC on your system.

If 2400 CFM was enough, they wouldn't have added another fan, and it would never come on. ;)
 
Just to muddy the waters -
I used to run an electric fan advertised at 2000 CFM full-time and when the ECM wanted it, the AC fan came on too.
It worked OK but it was definitely a lot less cooling power than the mechanical fan. The ECM had the AC fan on & off a lot, even in mild Oakland temperatures. In hot weather, it was on almost full time. Crawling, ditto.
I put a ZJ fan in & some water wetter. It has to be over 90 degrees before the AC fan comes on at all, and even then, i have to be climbing a 500 ft hill up a windy road before it will do it.
...
 
I gotta go with CAL & yossarian19. I was having cooling problems increase incrementally on my 96! I had a winch bumper and winch, added a rear 4 drawer tool box, then I switched to 36x15.50's from 35x12.50's and that killed it. I tried adding a Derailie trans cooler with the fan set up! Helped a little! I then cut hood vents in the hood, then bigger ones, no change occurred. Then I mounted the trans cooler to the hood under the vent to suck out the air, no good. Then I switched the two wires and flip the blade to draw in the air (blades were pitched), no good. FINALLY I bought a ZJ clutch fan. When I saw the difference in size, design, and resistance it blew me away! The XJ clutch was like a toy. After I installed it and before I drove it, I could see the difference in air circulation not to mention the sound of air being drawn. It was as loud as my Kenworth clutch fan, ok slight exaggeration but you get the point. I am thrilled with the $50.00 spent!!! Oh and I already had tried dual fans as well as combination of mechanical and electric together, separate one constant on one thermostatic, tried them as pusher, puller combinations on my 85 XJ and no good so I wasn't going down that road again!
 
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Why add a switch? particularly for full off? You're adding a point of failure who's only normal function is to make you overheat. :)

I think what you're failing to realize is that a triple 10" fan setup is barely adequate to cool a 4.0 in normal conditions. If you want to do it, do it, but don't put a bunch of work into complicating it or you'll just make it fail. Run 3 fans. Run them all the time. Run each on its own wiring and relay.

Most of the fan kits have a 3 pole switch. all on(in case the sensor dies or needed), all off, and through the sensor. I see your point and as long as the mech fan and ZJ clutch will give me enough room to not smack the rad i will run it.

You can sincerely believe that all day long. I have made *extensive* studies of the Cherokee cooling system, tried most combinations, and discussed the triple threat fan system with its designer at some length (he agrees it wouldnt keep my system cool). He was very forthcoming with the information he had, which I do like.

The fact is, my mechanical fan pulls ~4400 CFM at 3000 rpm on an anemometer, which is almost twice the max airflow of the triple threat kit. Thats without adding the electric aux fan that Jeep felt was necessary if you had even just AC on your system.

If 2400 CFM was enough, they wouldn't have added another fan, and it would never come on. ;)

I lurked around some other forums and never got that warm and fuzzy feeling that anybody had actual hard evidence of what the mech fan pulls. Lots of randomn numbers out there thats for sure. im in as long as it clears the rad. Its hard to not go with what you are saying, especially after going through your build threads. haha. Are you running the zj clutch and OE mech fan or something different?
 
I'm actually running no fan clutch now (it failed at a race so we ran screws through it).

The last time I had the winch off, we had the AC guy from work come by with his airflow meter and toss it up in front of the radiator. I'd been meaning to do it for a long long time..
 
You can sincerely believe that all day long. I have made *extensive* studies of the Cherokee cooling system, tried most combinations, and discussed the triple threat fan system with its designer at some length (he agrees it wouldnt keep my system cool). He was very forthcoming with the information he had, which I do like.

The fact is, my mechanical fan pulls ~4400 CFM at 3000 rpm on an anemometer, which is almost twice the max airflow of the triple threat kit. Thats without adding the electric aux fan that Jeep felt was necessary if you had even just AC on your system.

If 2400 CFM was enough, they wouldn't have added another fan, and it would never come on. ;)

I think it should be noted what the truck is doing and how the automatic transmission is being cooled - which I'm assuming both him and yourself are using. I am not doubting your experience, but the methodology in how you're suggesting he configure his cooling setup isn't in my opinion what I would suggest for a street/trail truck based on my experience with the 4.0L. I got no indication he was racing his truck or it was seeing mid to high RPM's regularly. Interesting notes about the triple threat fan system.

the 4400CFM is of course related to the environmental conditions for which you took the test but still an unrealistic figure to quote for a vehicle that never see's that kind of RPM for any length of time. If his truck is automatic, it spends most of its life below that RPM and especially when slow speed off-roaded, the CFM's are much lower. What would be interesting to know is where the fan's stall speed is and how the airflow relates to a particular RPM for the OE design - much more useful data. Every single fan design has a stall rpm range where performance falls off dramatically and their output curves are not necessarily linear. I used to design mechanical fan assemblies for air-assisted agricultural equipment and have sat with Multi-Wing fan design engineers on many projects. I was constantly surprised at the variances in performance. There are a lot of things more than (S)CFM that affect the performance of the cooling efficiency.

I still believe what I stated earlier was appropriate.
 
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I think it should be noted what the truck is doing and how the automatic transmission is being cooled - which I'm assuming both him and yourself are using. I am not doubting your experience, but the methodology in how you're suggesting he configure his cooling setup isn't in my opinion what I would suggest for a street/trail truck based on my experience with the 4.0L. I got no indication he was racing his truck or it was seeing mid to high RPM's regularly. Interesting notes about the triple threat fan system.

the 4400CFM is of course related to the environmental conditions for which you took the test but still an unrealistic figure to quote for a vehicle that never see's that kind of RPM for any length of time. If his truck is automatic, it spends most of its life below that RPM and especially when slow speed off-roaded, the CFM's are much lower. What would be interesting to know is where the fan's stall speed is and how the airflow relates to a particular RPM for the OE design - much more useful data. Every single fan design has a stall rpm range where performance falls off dramatically and their output curves are not necessarily linear. I used to design mechanical fan assemblies for air-assisted agricultural equipment and have sat with Multi-Wing fan design engineers on many projects. I was constantly surprised at the variances in performance. There are a lot of things more than (S)CFM that affect the performance of the cooling efficiency.

I still believe what I stated earlier was appropriate.

Im running a manual trans. I prefer to select my own gears/rpm instead of the vehicle trying to figure out what i need. lol. I do not plan on racing this thing but living next to the dunes and lots of open desert allows me to get up to a decent speed if i so desire. I am purposely overbuilding the cooling system so that whatever i end up deciding to do to this thing down the road ie crawl, race, dd, etc.. it will be ready. I bought the triple shroud because it was cheap and i thought it would be a good idea which it still may be. Im one of those cant leave well enough alone kind of guys and i have a few factory shrouds laying around from my motor swaps and i have a shiny new 16in flex a lite efan from a previous project so i can can do some playing around and see what i feel works best and run it. i have to admit that 10in efans do not have jack crap for advertised cfm, which is why i havent bought any yet.

you both have good points so I think you both won. lol
 
I'm actually running no fan clutch now (it failed at a race so we ran screws through it).

The last time I had the winch off, we had the AC guy from work come by with his airflow meter and toss it up in front of the radiator. I'd been meaning to do it for a long long time..

So your running straight factory fan? Yea i dont think i need all that. so its 4400 cfm in that setup? im curious as to what it is with the zj or xj clutch now. hmm...
 
I remember Dr Dyno (another poster on here, from UAE ) stating the XJ 4.0 clutch was good for 1750 CFM at idle. If true, it must ramp up substantially with engine speed because I found the 2000 CFM of my electric to be less effective than the mech fan.
 
I have to agree with cal on this. I doubt you are going to be able to control temps with electric fans in the desert. I have the ffdynamics tripple fan setup and untill recently it would always get hot if it was over 95. When it was 105 around here I and I had a trip over a couple miles I would always take my mustang because I knew my Jeep would overheat.

My previous cooling setup was ffdynamics aluminum radiator and three fan and shroud kit, hesco high flow pump, and run cool hood louvers. It was fine under 95 degrees, any hotter then that it would slowly raise in temp up to the red zone.

Being a stubborn bastard and refusing to throw away my electric fans I decided to purchase a expensive ass Griffin radiator, the same one Cal put in his rig, and also put BeCool coolant in it. Now my temps sit right at the 195 degrees my thermostat opens at.

I consider the CSF radiator you are putting in with the fans to be about the same quality as the ffdynamics one that I had and am sure you are going to have trouble with it. It would be fine if you kept the mechanical fan but with the reduced airflow from the electric fans it isn't going to work. The problem is with our short radiator we can only get 10" fans and they don't flow enough air. Too much of the radiator is covered by the fan motors. Especially to stay cool at 110 degrees ambient temperature.

Because you asked about controls...
I control my fans with a temp sensor from a SAAB that controls three 30 amo relays. I got a 1 1/4 x 4 brass nipple and drippled and tapped a hole in it the same size as the SAAB sensor. I then sliced the upper radiator hose and installed the nipple in it. I fed the temp sensor a ignition hot wire and when it gets up to temp it turns on the relays. It is an idea I stole from someone on here but for the life of me I can't seem to find the thread or remember who it was.

Good luck with your setup, but unless you feel like springing for a Griffin radiator I would recomend you don't do electric fans in your climate.

Also, I really didn't see any gas mileage or power increase from the elctric fans if thats what your going for, the only benefit seems to be they are quiet.
 
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