Improving the cooling on our TJs

[TexasTJ2004]

Now I need to install the Mopar radiator and finally expect some better cooling

 

[MountaineerTom]

Do you know the CFM difference between stock and the alternatives? I was under the impression that stock was as good or better than the Hayden clutches and Explorer fan, but I can't remember if the Derale 6-blade was discussed.

I don’t. I did see in a thread I asked some questions about the 6 blade fan, I’ll see if I can find it. My OEM clutch went out years ago and I replaced it with the Hayden 2771. Haven’t had any issues with it. I only tried the 2791 clutch and later the 6 blade fan to see if I could get the A/C a little cooler in the hot/humid summers here in the southeast. There was no noticeable difference in the A/C. Switched back to the OEM fan and 2771 that I had been using for quite some time.

I had no engine cooling issues with any of the setups. Just louder, engaged more and some drag on the engine.

 

[MountaineerTom]

I don’t. I did see in a thread I asked some questions about the 6 blade fan, I’ll see if I can find it.

@TexasTJ2004 found and posted what I was thinking of.

 

[TexasTJ2004]

I don’t. I did see in a thread I asked some questions about the 6 blade fan, I’ll see if I can find it. My OEM clutch went out years ago and I replaced it with the Hayden 2771. Haven’t had any issues with it. I only tried the 2791 clutch and later the 6 blade fan to see if I could get the A/C a little cooler in the hot/humid summers here in the southeast. There was no noticeable difference in the A/C. Switched back to the OEM fan and 2771 that I had been using for quite some time.

I had no engine cooling issues with any of the setups. Just louder, engaged more and some drag on the engine.

I came to conclusion that the problem with the AC is that there is no small dedicated electric fan for cooling the condenser. So what I did is removed the headlight and installed through the headlight hole couple of 6 inch electric fans that will cool the condenser itself. This way the AC works so much better.

 

[MikeE024]

Yes, @Davidtj did the comparison.
Here is his observations (copy pasted):

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

Nice! Hopefully it helps drop your ECTs next summer let us know how it goes

 

[MountaineerTom]

I came to conclusion that the problem with the AC is that there is no small dedicated electric fan for cooling the condenser. So what I did is removed the headlight and installed through the headlight hole couple of 6 inch electric fans that will cool the condenser itself. This way the AC works so much better.

That’s interesting. I just found your post in the improving the cooling thread with pics of your extra fans. I don’t think I’d have room to add any up there as I have a trans fluid cooler mounted on the V support.

That could be why I’m looking for cooler A/C…condenser sandwiched between two hot fluid coolers.

 

[jjvw]

Now I need to install the Mopar radiator and finally expect some better cooling

This is the key detail. After all of this, you still haven't addressed the fundamental issue with your cooling system.

 

[chili_pepper]

This is the key detail. After all of this, you still haven't addressed the fundamental issue with your cooling system.

Would that be the amount of airflow blocked from the items in front of the radiator?

 

[jjvw]

Would that be the amount of airflow blocked from the items in front of the radiator?

No. He needs to quit screwing around and simply put a Mopar radiator in there and return the cooling system to 100% factory.

 

[MikeE024]

This is the key detail. After all of this, you still haven't addressed the fundamental issue with your cooling system.

He’s aware, he’s just being hard headed about the radiator and tinkering because he can. We’re simply here for the ride.

Imo, it would be more fruitful if he was fully OEM as a baseline before going willy wonka to see what improvements can potentially be made.

 

[freedom_in_4low]

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

Just my .02, but if the fan was spinning different rpm that tells me the clutch was at different levels of engagement, rendering this not an apples to apples test. Need to measure cfm for both fans at the same fan speed. If anything, at the same air temp hitting the fan clutch, the 6 blade fan should be turning slower due to the additional power required to move more air.

 

[ChasUGC]

I have a 97 Wrangler 4.0L Automatic, Original Owner and Engine, and here is a picture of where my Coolant temperature gauge stays. If it changes, I start to get worried. On extremely hot days (greater than 95-100), stuck in freeway traffic, with the AC on, I did see it go slightly over 210). On that day, I turned the AC off, and rolled down the window and it went back down. When traffic started moving, I turned back on the AC, and it stayed there, as long as forced air was blowing over my radiator on the freeway. Gotta take care of her. She's a lady. She's a little rugged, but a lady all the same. lol.

 

[xXDavidCXx]

I have a 97 Wrangler 4.0L Automatic, Original Owner and Engine, and here is a picture of where my Coolant temperature gauge stays. If it changes, I start to get worried. On extremely hot days (greater than 95-100), stuck in freeway traffic, with the AC on, I did see it go slightly over 210). On that day, I turned the AC off, and rolled down the window and it went back down. When traffic started moving, I turned back on the AC, and it stayed there, as long as forced air was blowing over my radiator on the freeway. Gotta take care of her. She's a lady. She's a little rugged, but a lady all the same. lol.
View attachment 477135

Totally normal operation, turn that AC back on and forget about it

 

[MikeE024]

I have a 97 Wrangler 4.0L Automatic, Original Owner and Engine, and here is a picture of where my Coolant temperature gauge stays. If it changes, I start to get worried. On extremely hot days (greater than 95-100), stuck in freeway traffic, with the AC on, I did see it go slightly over 210). On that day, I turned the AC off, and rolled down the window and it went back down. When traffic started moving, I turned back on the AC, and it stayed there, as long as forced air was blowing over my radiator on the freeway. Gotta take care of her. She's a lady. She's a little rugged, but a lady all the same. lol.
View attachment 477135

That’s normal.

Also, I’ve seen my needle past the 210* mark when my scan tool reported a temp of 205*.

 

[TexasTJ2004]

Nice! Hopefully it helps drop your ECTs next summer let us know how it goes

Hayden 2791 + 6 Blade fan already improves the idle temperatures. With AC on or w/o AC on, with 75C ambient, after an hour of idling the ECT stayed at around 204F and the IAT (in my 2004 it is the temperature of the manifold) around 203F.
With stock fan and 2771 Hayden clutch, it would start slowing creeping up. I am sure that Hayden with 2791 generates far better airflow at idle RPM.
I still need to install the OEM radiator instead of autozone garbage, but even now it works far better than it did in the past.

 

[Rickyd]

with 75C ambient

 

[MikeE024]

View attachment 477724

Surely he meant F

 

[MikeE024]

Hayden 2791 + 6 Blade fan already improves the idle temperatures. With AC on or w/o AC on, with 75C ambient, after an hour of idling the ECT stayed at around 204F and the IAT (in my 2004 it is the temperature of the manifold) around 203F.
With stock fan and 2771 Hayden clutch, it would start slowing creeping up. I am sure that Hayden with 2791 generates far better airflow at idle RPM.
I still need to install the OEM radiator instead of autozone garbage, but even now it works far better than it did in the past.

Haven’t had the AC on in a while, but I don't go over 205* in 75*F in idle. It reads closer to the thermostat rating at this time of the year.

 

[TexasTJ2004]

View attachment 477724

Yeah, the F got mistakenly replaced by C

 

[TexasTJ2004]

He’s aware, he’s just being hard headed about the radiator and tinkering because he can. We’re simply here for the ride.

Imo, it would be more fruitful if he was fully OEM as a baseline before going willy wonka to see what improvements can potentially be made.

I agree with you on the need to install the OEM radiator. I think that OEM radiator with Hayden 2791 and the 6 blade fan, will be the perfect combo.