Secondary Radiator Fan (Electric)

[Fouledplugs]

What is the purpose of adding another fan?

Im sure your question was directed at OP. But here in the south (Alabama) having an electric fan with more CFM capabilities is beneficial for A/C performance. It’s a different kind of hot here in the summer, humidity is the killer IMO. Having an electric fan is a go to route for some Jeep/crawlers here that have A/C and are often rolling slow or idling through trails. More CFM on the elctric puller or pusher fan is beneficial and oays dividends on those really hot days.

Like I mentioned its a common swap on the 4.0’s in my area where crawling is so popular.

Not to mention depending on the fan setup, they clean up the engine bay.

Hard to tell but were you asking in a rhetorical question way?

 

[Fouledplugs]

Why do you want an electric fan? What are you hoping to accomplish with that?

If the answer is that you want it to run cooler, that's not a good thing. All vehicles have an operational temperature range that they are supposed to run in (and the ECU expects them to be running in) for the best fuel economy, emissions, and power. If you make it run cooler than that, you're essentially never letting your engine get up to the correct operating temperature, and therefore you're doing more harm than good.

If the answer is that you want to squeeze a few more horsepower out of it, that's a waste of time and money. The amount of parasitic drag you'd free up by removing the fan clutch and replacing it with an electric fan is negligible at best. You MAY gain 1-2 hp at a specific RPM, but it will be negligible horsepower, unfelt power gains, and arguable gains at best (you'd have to do a series of dyno runs both before and after the conversion to accurately measure any gains).

Anyways, long story short, this is a huge waste of money, a huge one. Don't fall into the myth that electric fans are better.

This thread is worth a read as well: The myth: low temp thermostats, electric fan conversions & "performance" radiators

You seem to have quite the grasp on electric fans and their effect on factory cooling systems, any idea why Jeep went with an electric fan setup from the factory on certain engine packages like the 4 cylinder offering in the TJ?

This may help with that putting the electric fan myth theory to bed.

@Jerry Bransford please feel free to chime in as well if you have any knowledge as to why Jeep ditched the mechanical fan on certain models And instead engineered an electric solution. The engineers must have found the electric fan more beneficial than a mechanical fan.

 

[Stockli]

Personally I like the assurance of a mechanical fan.

I have seen many electric fans just die. Some taking the radiator with them. It’s not often a mechanical fan will go out completely and leave you completely stranded. Even if you threw a belt.

Electrics may do just that.

 

[Chris]

You seem to have quite the grasp on electric fans and their effect on factory cooling systems, any idea why Jeep went with an electric fan setup from the factory on certain engine packages like the 4 cylinder offering in the TJ?

Being as though the 4 cylinder TJ engine was found in other vehicles aside from the TJ (PT Cruiser for instance), it's more than likely that that engine wasn't designed with a mechanical fan due to clearance issues. Because of this, they put it in the TJ with an electric fan, as it made no sense to re-engineer it for a mechanical fan just for the TJ platform.

That's only speculation, but I'd be willing to bet that's what the reason is. The 4.0 on the other hand was never offered in any vehicles that were tight on engine bay space. All of the vehicles the 4.0 came in had plenty of room under the hood for a mechanical fan, hence I don't think they ever had to design it with "space" in mind in the first place.

Again, only speculation, but it's just a thought.

I've been down the electric fan path with previous performance vehicles such as BMW M cars. There's no power to be gained, and unless you have a specific application that requires converting to an electric fan (i.e., a supercharger being in the way of the fan), then it's nothing more than a waste of time and money.

 

[Fouledplugs]

Personally I like the assurance of a mechanical fan.

I have seen many electric fans just die. Some taking the radiator with them. It’s not often a mechanical fan will go out completely and leave you completely stranded. Even if you threw a belt.

Electrics may do just that.

Same assurances applies to electric fuel pumps. More folks should swap in a mechanical for extra assurance. Ive seen tons of electric fuel pumps die, often leaving the driver/owner stranded.

Couldnt help myself here. But it is true.

 

[jjvw]

Im sure your question was directed at OP. ...

Hard to tell but were you asking in a rhetorical question way?

My question is directed to those who feel the need to add to or change the factory cooling system. I am assuming those that do (including those in Alabama) had factory cooling systems that were in otherwise good repair and were still not adequate. Is this correct?

 

[mrblaine]

You seem to have quite the grasp on electric fans and their effect on factory cooling systems, any idea why Jeep went with an electric fan setup from the factory on certain engine packages like the 4 cylinder offering in the TJ?

This may help with that putting the electric fan myth theory to bed.

@Jerry Bransford please feel free to chime in as well if you have any knowledge as to why Jeep ditched the mechanical fan on certain models And instead engineered an electric solution. The engineers must have found the electric fan more beneficial than a mechanical fan.

The better question is why they swapped to electric with some engines and not others. The smaller displacement 2.4 got the electric so they had the tech to do it, why didn't they go ahead and convert the 4.0 in the same year and later years to have one? They had the fan, controller, shroud, harness, and radiator, why didn't they swap over?

 

[mrblaine]

Same assurances applies to electric fuel pumps. More folks should swap in a mechanical for extra assurance. Ive seen tons of electric fuel pumps die, often leaving the driver/owner stranded.

Couldnt help myself here. But it is true.

And, I've seen lots of mechanical pumps die. Where and how do you run a mechanical on a 4.0 in a TJ? That said, I've been on the trails with a wide variety of TJ's since we bought our first one in 99. I've been involved in lots of repairs for various bits of carnage and failure, a dead electric fuel pump isn't on that list. Not saying it can't or hasn't happened, I've just never seen it and I've wheeled with some folks who run 15 gallon tanks that started as 19's.

 

[mrblaine]

Being as though the 4 cylinder TJ engine was found in other vehicles aside from the TJ (PT Cruiser for instance), it's more than likely that that engine wasn't designed with a mechanical fan due to clearance issues. Because of this, they put it in the TJ with an electric fan, as it made no sense to re-engineer it for a mechanical fan just for the TJ platform.

That's only speculation, but I'd be willing to bet that's what the reason is. The 4.0 on the other hand was never offered in any vehicles that were tight on engine bay space. All of the vehicles the 4.0 came in had plenty of room under the hood for a mechanical fan, hence I don't think they ever had to design it with "space" in mind in the first place.

Again, only speculation, but it's just a thought.

I've been down the electric fan path with previous performance vehicles such as BMW M cars. There's no power to be gained, and unless you have a specific application that requires converting to an electric fan (i.e., a supercharger being in the way of the fan), then it's nothing more than a waste of time and money.

Ever look under the hood of an XJ?

 

[Chris]

Ever look under the hood of an XJ?

It's been around 7 years since I sold my XJ, so not for a long time. However, after just looking one up in a Google search, that engine bay is a lot more pressed for space than I obviously remembered!

 

[Fouledplugs]

My question is directed to those who feel the need to add to or change the factory cooling system. I am assuming those that do (including those in Alabama) had factory cooling systems that were in otherwise good repair and were still not adequate. Is this correct?

yes and no. As far as engine cooling goes, the factory mech. fan is more than adequate for keeping the engine temps in a factory range.

Replacing the factory mechanical fan with an electric fan for better A/C performance did show to be somewhat benificial in long slow summer time trail rides, maybe it's the humidity. Although I have never done an actual back to back comparison with a thermometer. So let it be known that only a butt dyno was used.

 

[Fouledplugs]

And, I've seen lots of mechanical pumps die. Where and how do you run a mechanical on a 4.0 in a TJ? That said, I've been on the trails with a wide variety of TJ's since we bought our first one in 99. I've been involved in lots of repairs for various bits of carnage and failure, a dead electric fuel pump isn't on that list. Not saying it can't or hasn't happened, I've just never seen it and I've wheeled with some folks who run 15 gallon tanks that started as 19's.

I was being a smart a$$ and using that technology as an example with his theory applied.

 

[Fouledplugs]

The better question is why they swapped to electric with some engines and not others. The smaller displacement 2.4 got the electric so they had the tech to do it, why didn't they go ahead and convert the 4.0 in the same year and later years to have one? They had the fan, controller, shroud, harness, and radiator, why didn't they swap over?

true, thats a good question that I wish we had a TJ/LJ engineer around for.

 

[Davidtj]

Im sure your question was directed at OP. But here in the south (Alabama) having an electric fan with more CFM capabilities is beneficial for A/C performance. It’s a different kind of hot here in the summer, humidity is the killer IMO. Having an electric fan is a go to route for some Jeep/crawlers here that have A/C and are often rolling slow or idling through trails. More CFM on the elctric puller or pusher fan is beneficial and oays dividends on those really hot days.

Like I mentioned its a common swap on the 4.0’s in my area where crawling is so popular.

Not to mention depending on the fan setup, they clean up the engine bay.

Hard to tell but were you asking in a rhetorical question way?

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

 

[Fouledplugs]

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

This is all great stuff! Anxious to hear what kind of improvments you get next summer.

 

[mrblaine]

This is all great stuff! Anxious to hear what kind of improvments you get next summer.

I run the 7 blade fan and correct clutch on Kat's. Like the electric fan question, why wasn't it carried forward on all models after the TSB? Obviously they solved the problem another way and if you read the TSB for it, there is some flashing done to the PCM to go with the install. It is not a blanket solution. I also have a spare set in case.

 

[Jcrubicon]

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

What’s was the verdict on the derale fan did it help idle temps with the ac on?

 

[Jcrubicon]

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

Here in Florida its hot also try crawling on trail or hwy. when its 97 + 100 % humidity the A/c just doesn't cut it . Which since you brought it up I have been working on a cooling mod.
Let me state from beginning my Jeep doesn't not over heat runs right at 210 in summer as many recommend I am just trying this to improve A/c performance.
After doing a lot of research I found jeep had a 7 blade fan and HD clutch for the TJ available at one time. The update was short lived and parts are not currently available
PN: 55037650AA, Fan 7-Blade,
PN: 05066177AA, HD fan clutch
I am not shure why program from Chrysler was discontinued, probably felt wasn't needed since right around time it was discontinued they came out with single core radiator which improved on existing. I do know Tj engine bay gets hot Eg heat sock on injectors etc.
I start looking for alternatives to get a little more air flow on A/C condenser when idling etc.
I found some people were recommending a 9 or 10 blade fan from explorer before they went to electric fan I looked at those however is a plastic blade and could not find any data on blade performance one person stated had converted and worked great even without fan shroud
(don't know why you would run without shroud makes no sense)

I found Derale sold a 18 inch reverse rotation 6 blade steel fan
Pt# 17918 I ordered one and Hayden HD clutch pn#2771
Before removing my old fan I did some testing for comparison
When I received new fan was impressed by quality of part made in USA very nice and looked heavy duty ( I have used Derale trans coolers before consistently have a good product)
In comparison to my 5 blade noticed besides extra blade new fan had less pitch, began to wonder if would make a difference, called Derale while they didn't have fan curve data, they did tell fan me was designed to produce 500 to 750 cfm more then stock
This is my test data before and after using Fluke 922 airflow meter
orginal idle 450 cfm 0.21 static
1200 rpm standing 700 cfm 0.35 static
6 blade idle 635 cfm 0.36 static
1200 rpm 1020 cfm 0.48 static

This project I have been thinking about for a while however never got installed until recently now weather is cooler so will have to wait to produce more data on A/c performance at higher temps etc. this was done first of Nov at 83 degrees
I am hoping by getting more airflow over A/c condenser as to dissipate heat a little faster

What’s was the verdict on the derale fan did it help idle temps with the ac on?

 

[Davidtj]

Yes I can sit in traffic with A/c on blowing out 39/42 degree air and engine temp according to OBD scanner under 200

 

[C.J. Roberts]

Yes I can sit in traffic with A/c on blowing out 39/42 degree air and engine temp according to OBD scanner under 200

Which is too low for the PCM. As stated before, engine temp should be 210.