I can tell for sure that with fan and Hayden 2791 fan clutch even with my auto zone crap radiator, it still cools fine. Let's see when the weather gets hotter.
Improving the cooling on our TJs
- Thread starter TexasTJ2004
- Start date
I can tell for sure that with fan and Hayden 2791 fan clutch even with my auto zone crap radiator, it still cools fine. Let's see when the weather gets hotter.
Jcrubicon
Member
How well does your Hayden function I switched to a usmw 22159 because the Hayden’s that I had were terrible they work for a couple months max then stay locked on the usmw is also USA made. It functions absolutely perfect, shuts off shortly after start up and turns on at 215 and stays on until 200 then disengages it’s also a severe duty equivalent to the 2791.
The combo of 2791 with Derale 6 blade fan works perfectly fine. Meanwhile even when long idle the engine temperature stays under 210, more in the area of 204-208. This is in Houston Heat.
The transmission maximum when idling for 2 hours reached 178, and seems like derale transmission cooler kicks in and starts cooling.
I am still running autozone garbage radiator, so it seems like adding a better clutch (2791) with 6 blade fan works great
Jcrubicon
Member
The combo of 2791 with Derale 6 blade fan works perfectly fine. Meanwhile even when long idle the engine temperature stays under 210, more in the area of 204-208. This is in Houston Heat.
The transmission maximum when idling for 2 hours reached 178, and seems like derale transmission cooler kicks in and starts cooling.
I am still running autozone garbageradiator, so it seems like adding a better clutch (2791) with 6 blade fan works great
Interesting I did some of my own testing today around 90 degree ambient temp outside. I then idled my jeep for about 45mins after reaching operating temperature with the ac running at full blast I used my obd scanner to measure engine coolant at 226 degrees using a oem radiator and water pump and a Derale 17918 fan and usmw 22159 fan clutch. This might seem high to some but the temp always creeps over time on my jeep at idle and usually into the 230s. As of right now I would say there is minor improvement with this 6 blade fan but I find the it has less turbulent flow but also takes longer to disengage the fan clutch in normal driving situations. Maybe it do to be symmetrical? I ordered a 17919 fan for testing I think with minor fan shroud modifications (shifting mounts to center the fan in it) it will fit without interference and not only provide more surface area for airflow but tighter tolerances at the shoulders of the fan blades resulting in a more efficient setup overall I will report back with more information as I get it.
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LONGJP2
TJ Expert
What switch did you end up getting, and did it fit the Derale fitting?
I one I tried did not have the right thread pitch.
Jcrubicon
Member
When I was using the e fan from derale I used a 210 on 195 off switch from American volt it didn’t fit the fitting from the kit but a basic brass t fitting from ace hardware was easy to fine and I was able to adapt it no problem.
All in all the mechanical fan is still definitely the best option my e fan now sits in the garage
https://senasys.com/product/430-301a6-12-auto-reset-thermostat/
This is the only company I found selling what we need. I went with the 150* instead of the 170* option to play it safe after my poor experience with the Derale switch. It's much more accurate and reliable so you might be good with the 170* switch.
Alternatively, they can make a custom 160* or 165* version if you want one, but that requires a set-up fee (around $35 at most iirc for the set-up).
Jcrubicon
Member
Why run such a low temperature on the switch the factory thermostat opens at 192-195f so the coolant temp should never really fall below that if it’s functioning properly. If you use that temp range the fan will likely never turn off once it turns on. Also it’s not advisable to run a lower temperature thermostat because the ecu fuel and ignition tables are designed to operate at the factory range.
I think he's talking about the Derale thermostat, not the engine.
Because it helps keep the trans fluid temps from getting well past the coolant temps. And it helps slow the rate at which the fluid temps rise to or past the coolant temps.
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Jcrubicon
Member
Ahhhh sorry I did realize yall were talking about a trans cooler
I’m still stuck on engine cooling. I have an E fan from derale that uses the same type of switches. Sorry for the confusion.Ahhhh sorry I did realize yall were talking about a trans cooler
All good man, you were just trying to keep us from doing something silly
Jcrubicon
Member
I install the 19in fan today it fits but I did have to redrill the shroud mounting holes pulls a noticeable amount of air at idle I will update with more testing later.
Jcrubicon
Member
Did some testing today at 85f with the 19in fan and usmw 22160 fan clutch after 45 mins of idling and the ac on full blast she topped out at 210! Massive improvement! so far this is looking promising! Tomorrow will be in the 90s I will post again with this results. Cheers!
85 is not a challenge for a properly operating cooling system.
Did you have poor results at that temp on the stock blades?
Did you have poor results at that temp on the stock blades?
Yea man, the ETCs were tested pretty good idling with the AC on last summer in PHX (118* outside).
Jcrubicon
Member
Yes on a 90+ day idling with the ac on for extended periods of over 30min I could see temps over 230 I’m not talking about the gauge in the jeep it barely ticks over 210 at that temp also I have all new oem cooling components so not sure where all this extra heat is coming from but it’s definitely there
Jcrubicon
Member
When I was in Moab I saw 240s on a 107 degree day also my temp are always stable until the ac is maxed out then the system heat soaks and climbs I have always seen this as an issue on my Tj? It always chalked down to not enough airflow at idle
Dang man. I have two coolers in front of the condenser, but I haven’t seen mine get that high. I don’t rely on the stock gauge either.
Is your fan clutch pulling sufficient air? If you have a meter for checking CFM we can compare if you’re interested.
I’ve have flakes plug up a newish Mopar radiator but that also caused high temps when sustaining a fast highway speed.
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