So Cal desert rats

[XJrealm]

" Stock XJ Clutch fan pull 2,000 CFM.
Stock XJ auxiliary E-fans pull 1,350 CFM."
This is a real world test!!! Not speculation. The same person tested post a triple threat install and he measured 3400cfm total. I don't know if he has ffdynamics or dirtbound setup, however these are real numbers measured with the same tool. I have not found a cfm rating with the zj clutch though.

Been doing lots of reading and I found this on naxja. I also found that per manufacture, the xj requires 2000cfm for light use and 3000cfm for heavy use/offroad/towing. This means if my fans are actually putting out 3300cfm, I don't have an airflow problem.

 

[Xtreme XJ]

If You decide to go ZJ, let me know. There was a small mod I had to do, not bad at all but easier with the right dremel tips on hand.:wave: It increases the fan to crank rotation from 60-70 % to 80-90%. Worth it out here. My success was not one thing but a bunch of things...Remember?

I've been running the ZJ one for 3 or 4 years now...

Curt

 

[Paul Airhart]

I guess it just depends where you read. I also found a write up where a fella did the math, but I could not find it again. Don't know what it would be with the ZJ vis clutch. Don't shoot the messenger, I'm just trying to help.

Re: 2 Factory electric fans
The problem in doing so is that the stock mech fan pulls about 4K CFM where as our e-fans pull around 2K ( a little less IIRC) So by pulling your Mech fan in place of a stock on your losing roughly 2K CFM in the process...

http://www.naxja.org/forum/showthread.php?t=991837

 

[Paul Airhart]

I've been running the ZJ one for 3 or 4 years now...

Curt

Aaaah, nevermind :wave1:

 

[Paul Airhart]

Something else I noticed, out of all the write-up's I read, not one took into consideration the geographical location. The post's I read where the poster was saying "these things are great..." were posting from Minnesota or a state with similar weather patterns.

 

[XJrealm]

Sorry paul, I'm not mad, and I appreciate your help! I'm just frustrated that everyone is stuck on the fans because they really don't have anything to do with anything when you are driving 70mph down the freeway. I have not read one post from anyone that would argue that fact! So if I am overheating on the freeway when I have all that ram air, it tells me I have a problem somewhere else. Yet everyone is going back to the fans!

 

[Xtreme XJ]

" Stock XJ Clutch fan pull 2,000 CFM.
Stock XJ auxiliary E-fans pull 1,350 CFM."
This is a real world test!!! Not speculation. The same person tested post a triple threat install and he measured 3400cfm total. I don't know if he has ffdynamics or dirtbound setup, however these are real numbers measured with the same tool. I have not found a cfm rating with the zj clutch though.

Been doing lots of reading and I found this on naxja. I also found that per manufacture, the xj requires 2000cfm for light use and 3000cfm for heavy use/offroad/towing. This means if my fans are actually putting out 3300cfm, I don't have an airflow problem.

Hmmmm... Max got more in his testing...
http://www.naxja.org/forum/showthread.php?t=1057920&page=2&highlight=Dirt+Bound+fan

I too could very well have more going on with the motor as opposed to the airflow/rad/ issue... but I really don't want to know...

Curt

 

[Paul Airhart]

That's a good Q. How big is the hole in Your fan shroud's? The mechanical has an opening eprox. 11"X 13" and the e-fan 11"X 12"

 

[O-TAY XJ]

With the three fans across your rad. you are pulling more air thur the rad. than with a stock set up. So the air flow should be OK. From looking at your coolant it appears you have oil in it. This is not good. As far as the water wetter goes I had a three core copper rad. started to run hot so I put the water wetter with new coolant in it didn,t help but my coolant didn't have the junk floating it. It look like reg. coolant. I put a 2 core ALM. rad in about 2 yrs. ago still working good. Mine is a "92" with the stock fan and the stock late model ele. fan. On a 115 degree day it will run 220-225 with a/c in town. Did you check your oil filler cap after driving to see if it had any white foam on it? You can also pull the oil drain pug after it sets over night to see if you have water in the oil. Maybe you will luck out and just have a bad head gasket.

 

[Xtreme XJ]

Whether air flow is the problem or not the CFM #s with stock compared to the 3 fan set up looks like a 2000 CFM drop (approx.) FF vs. stock...

How do you come up with this Bill ??
"With the three fans across your rad. you are pulling more air thur the rad. than with a stock set up"

Curt

 

[O-TAY XJ]

With the three fans more area of the rad. is covered. It appears the ele. have more CFM than stock.

 

[TheCaptain]

Like i said before, i switch back to the mechanical fan during the summer...

From my experience running the electrics (dirtbound) for the last 2 years: The electrics pull more CFM at idle and low speeds, this makes them perfect for crawling and general use during the cooler months of the year. On warmer days (80+) i still have freeway temps in the 220-230 range.

Once summer hits, i switch to a ZJ clutch w/ stock blade and Aux fan. The first start after installing the "stock" setup, i get a cloud of dust that is pulled from the radiator because the CFM difference is enormous. Temps return to normal, i can drive on the freeway and run my AC.

Winter/Fall/Spring (Electric)
The Good:
Less Noise
Better cooling while crawling
The Bad:
N/A

Summer (stock)
The Good:
Capable of Highway Speeds
A/C!
The Bad:
Noise (the ZJ clutch makes it sound like a turbo-prop plane taking off)
Less cooling while idle/crawling (although its still within safe limits)

 

[XJrealm]

Like i said before, i switch back to the mechanical fan during the summer...

From my experience running the electrics (dirtbound) for the last 2 years: The electrics pull more CFM at idle and low speeds, this makes them perfect for crawling and general use during the cooler months of the year. On warmer days (80+) i still have freeway temps in the 220-230 range.

Once summer hits, i switch to a ZJ clutch w/ stock blade and Aux fan. The first start after installing the "stock" setup, i get a cloud of dust that is pulled from the radiator because the CFM difference is enormous. Temps return to normal, i can drive on the freeway and run my AC.

Winter/Fall/Spring (Electric)
The Good:
Less Noise
Better cooling while crawling
The Bad:
N/A

Summer (stock)
The Good:
Capable of Highway Speeds
A/C!
The Bad:
Noise (the ZJ clutch makes it sound like a turbo-prop plane taking off)
Less cooling while idle/crawling (although its still within safe limits)

Thanks for chiming in Aaron 1. No offense to others I just nice to have a voice with actual experience. I give in and am on my way now to pick up a zj fan clutch. Ill give it one last go, if this doesn't fix it, it is going to stans auto

 

[Vanimal]

fyi, i couldnt get my fan clutch in without machining a little off the fins. my motor mounts are probably shot so that might have had something to do with it.

 

[O-TAY XJ]

Thanks for chiming in Aaron 1. No offense to others I just nice to have a voice with actual experience. I give in and am on my way now to pick up a zj fan clutch. Ill give it one last go, if this doesn't fix it, it is going to stans auto

Good to hear from someone who has been there and done that!!

 

[TheCaptain]

Here is the Napa part number: #272310

 

[Paul Airhart]

fyi, i couldnt get my fan clutch in without machining a little off the fins. my motor mounts are probably shot so that might have had something to do with it.

I had to do the same to get the clutch to mate to the fan. I just used a dremel and it only took a few minutes.

 

[Vanimal]

I had to do the same to get the clutch to mate to the fan. I just used a dremel and it only took a few minutes.

i had no problems with that, it was the clearance between the motor and radiator that was the issue.

 

[XJrealm]

Here is the Napa part number: #272310

That's what I just got! I'm on my way home now to drop it in, ill hit u up paul if I find clearance issues.

 

[Paul Airhart]

Hmmm, I had no problem with that clearance. See in the pic above, where the fan blade, closest to the center comes close to the fins on the clutch, mine hit those and I had to clearance the fins so the fan could drop all the way to where the fan and clutch mates. Different years have different fans I guess.