Secondary Radiator Fan (Electric)

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
 
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The stock setup should be fine for 99% of us. The only reason I could ever see needing to upgrade your radiator, fan, and cooling system, would be if you did an engine swap (i.e. a V8 conversion).

Other than that, there's many guys that do a lot of slow crawl rock climbing down in the intense heat and conditions of Johnson Valley, California such as @Jerry Bransford. They're using the factory cooling system (and fan) and have no issues whatsoever.

I think the real key here is to make sure you have a cooling system that is maintained and taken care of. In other words, if your cooling system has 120k miles on it and no history of it ever having been maintained, it's probably time for a cooling system overhaul, using replacement factory parts.
 
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The only possible reason I can think of for replacing the stock fan with an electric is if you do a LOT of water crossings where you can get your stock fan into the water, possibly causing damage. But, there is more to water crossings and fording than swapping out the mechanical fan for an electric. An auxiliary electric fan is unnecessary on the TJ.
 
Temp hovers around 205... but just seems hotter and takes a while for the temp to come down after turning off the engine...

Not interested in any go gain by removing the clutch fan....

Just wanna manage the temp on slow roll days on the trail....
 
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G-Whiz said:
Temp hovers around 205... but just seems hotter and takes a while for the temp to come down after turning off the engine...

Not interested in any go gain by removing the clutch fan....

Just wanna manage the temp on slow roll days on the trail....
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That's not a bad temp to run at. Your Jeep should be running about 210F once it's warmed up. That's just where the factory designed them to run.
 
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G-Whiz said:
Temp hovers around 205... but just seems hotter and takes a while for the temp to come down after turning off the engine...

Not interested in any go gain by removing the clutch fan....

Just wanna manage the temp on slow roll days on the trail....
Click to expand...

210 is perfect and it really shouldn't be dropping below that ... ever. And really, who cares how long it takes once the vehicle is turned off?
 
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G-Whiz said:
Temp hovers around 205... but just seems hotter and takes a while for the temp to come down after turning off the engine...

Not interested in any go gain by removing the clutch fan....

Just wanna manage the temp on slow roll days on the trail....
Click to expand...

Pop the hood and let some of the trapped hot air out and it will cool down quicker, if it's a concern.
 
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Yep, 210 is what you should be running at (around there). You don't want it to run any cooler than that. The PCM (ECU) is expecting it to run at around those temps.

I'm only stating the truth. I see some guys convert to electric fans, but I can assure you, it's quite possibly one of the biggest wastes of money you could spend when it comes to modifying our TJs.

Let's put it this way: If the Jeep engineers designed your engine to sit in 120 degree Arizona weather in stop-and-go highway traffic—with the air condition on, without overheating—, well then you're more than fine slow crawling over obstacles off-road.
 
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X2, forget that mod. As above, the OE cooling system is more than up to keeping everything cool on the hottest days out in the desert. 210 is absolutely normal, that's what mine runs at when it's over 100 and I'm doing low-speed rock crawling in the desert.

Any time your engine starts running hotter than it should, it's not the design. It is always caused by a fixable problem... clogged radiator, bad fan clutch, stuck thermostat, mud in the radiator, or bad water pump. To help keep your radiator from clogging, keep the coolant fresh and NEVER use tap water to mix with the coolant. Tap water has dissolved mineral deposits (lime, calcium, etc.) in it which will build up inside the radiator. Instead, use distilled water which is sold by the gallon in your local grocery store's water aisle. Zerex G-05 is a good coolant to use, better auto parts stores like NAPA carries it. You won't find G-05 in low-end auto parts stores like Autozone. Autozone refuses to carry the good stuff like that. ;)
 
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Not sure if the winch may also be blocking air flow at normal driving speed; but it blocks about 1/3 of the grill openings:
20170612_153554.jpg


That's all my jeep drinks! Lol

But I just bugs me that the engine / engine compartment is just so hot....

What about a aftermarket hood vent??? Thoughts on that????
20170612_153054.jpg
 
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G-Whiz said:
But I just bugs me that the engine / engine compartment is just so hot....
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It's probably pretty close to 200 in there. ;) No vent is needed, nor would the engine run any cooler if the hood was vented. Us humans don't like the engine compartment's temperature but everything the factory installed in there is fine with it. :)
 
Jerry Bransford said:
It's probably pretty close to 200 in there. ;) No vent is needed, nor would the engine run any cooler if the hood was vented. Us humans don't like the engine compartment's temperature but everything the factory installed in there is fine with it. :)
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There are very few components under your hood that would not live longer and function better at a cooler temp then those normally generated by slow crawling trails in even 90 degree outside temps. Electric fans produce much more airflow thru your radiator at slow engine speeds. They also do not drive there blades into the radiator when making deep water crossings. That's when fans try to become propellers and bad things go bad quickly. Heat soaked injectors common to the 4.0L engines can also be greatly reduced with a vented hood. The ability to quickly detect a underhood fire is a side benefit which should not be overlooked while deep woods wheeling.
 
G-Whiz said:
Temp hovers around 205... but just seems hotter and takes a while for the temp to come down after turning off the engine...

Not interested in any go gain by removing the clutch fan....

Just wanna manage the temp on slow roll days on the trail....
Click to expand...
@G-Whiz you might want to research something called a timed relay. Idk enough to explain, but it keeps your oem fan running a couple minutes after you shut down the engine.
Im thinking of getting my jeep a timed relay for Christmas :)
 
KCsTJ said:
@G-Whiz you might want to research something called a timed relay. Idk enough to explain, but it keeps your oem fan running a couple minutes after you shut down the engine.
Im thinking of getting my jeep a timed relay for Christmas :)
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woudnt this be more of an elctric fac thing? i cant see the fan thats ran by the engine haveing this capabilty. then again i could be wrong its happened in the past
 
Just swap in the 2.4 or the 2.5 electric fan kit. Sorry, I can’t remember which engine 4 cylinder package comes with the electric fan kit from the factory. Its a common swap for 4.0’s and its factory Mopar stuff.
 
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