Two piece fan shroud modification

jeepdan · **Posted:** Sun Jun 23, 2013 10:50 am

I just finished the fan shroud modification as illustrated by "irunmiles" in the tech section.
I works so well! Even fiddling with AC lines isn't a problem :BANANA:

Why in the heck, didn't Jeep make it like this in the first place :evil:

I guess they were expecting to sell replacement AC lines and radiators damaged by frustrated mechanics.
One suggestion I add, is using 1/4" lock nuts with the nylon inserts, since you are bolting through plastic.
The next time that you have your CRD's fan shroud off, DO THIS MOD.

geordi · **Posted:** Sun Jun 23, 2013 11:22 am

A different way of doing this mod (and I agree with you - Why didn't Mopar do this from the factory) is to simply cut the plastic shroud below the two mounting bolts that thread into the pockets of the radiator. The bottom half can be left in place, or can be discarded. Then the top is free to be removed when needed.

jeepdan · **Posted:** Sun Jun 23, 2013 11:56 am

geordi wrote:

A different way of doing this mod (and I agree with you - Why didn't Mopar do this from the factory) is to simply cut the plastic shroud below the two mounting bolts that thread into the pockets of the radiator. The bottom half can be left in place, or can be discarded. Then the top is free to be removed when needed.

That would merely make into into a safety guard and you would loose the shroud's ability to help the fan move air.
Admittedly, that may not a problem in most applications though. The one CRD that I have, which I don't pull a trailer with, went a year without it's shroud on at all. Where I live, we very rarely have traffic jambs, where I might be sitting in traffic for long period of times in hot weather with the AC on.

geordi · **Posted:** Sun Jun 23, 2013 1:31 pm

The 'ability to move air' of that shroud is subject to much discussion.

Most other vehicles that have fans behind the radiator choose to mount them MUCH closer to the radiator than the CRD has it. The shroud also is a closer fit. I tend to think that the plastic V6 fan is a better option because it fits closer to the shroud, and more blades means more suction as there really isn't many places where a blade "isn't" while it is spinning. Less time between blade passes at a given point in space, should equate to a more constant flow of air. With the big blades, they have more of a space in between each blade, potentially leading to more 'rest time' for the airflow and reduced suction.

This makes sense in my head, I hope it makes sense here. Basically - with this current design, I don't think having the shroud helps or hurts much. I don't think it does much at all. An optimal setup would instead be the fans from the normal V6 / 4 cylinder gas versions - radiator-mounted pancake electric fan in a full-width close-fitting shroud enclosure.

flash7210 · **Posted:** Sun Jun 23, 2013 1:47 pm

I've been driving around for a year now with no engine driven fan.
Only the electric fan.
No overheating, but then I don't tow either.

DOC4444 · **Posted:** Sun Jun 23, 2013 4:24 pm

Keith told me that during initial development of the KJ CRD for MOPAR, they replaced the nylon V-6 fan with the metal one our rigs came with because it moves more air. (Then, of course, they put in a fan clutch that does not work.)

I use the nylon fan because it moves less air, but when combined with the Hayden clutch, engages at much lower temps. The idea is to catch the temp rise when towing earlier, so it never gets very hot. And, at the same time, to offset the potential loss in power/mileage from running a higher percentage of time with the fan clutch engaged.

DOC

jeepdan · **Posted:** Mon Jun 24, 2013 12:09 am

All good info.
I'm still, just happy as heck, that I don't have to wrestle that #$%^&* fan and shroud out together with very little room to work.

papaindigo · **Posted:** Mon Jun 24, 2013 8:25 am

There are several options on modifying the fan shroud to make access easier. Assuming a functional mechanical fan and fan clutch the all work fine. See my post further down on irunmiles post at viewtopic.php?f=98&t=64278&p=709322#p709322 . Some even run with no shroud and no mechanical fan but I'm not willing to go that far.

jeepdan · **Posted:** Mon Jun 24, 2013 11:41 pm

I would still recommend the irunmiles mod to anyone. It's easily done, maintains the stock design, and if done with some care, doesn't look like a "jury rig" job. It's a mod that I could do to someone else's vehicle if asked to do so, and feel fine with it.

irunmiles · **Posted:** Tue Jun 25, 2013 7:14 pm

I came up with the shroud mod after poking a hole in my radiator while trying to replace the fan clutch with the shroud in place. Glad others are finding it useful. My tank is still rollin at 205k miles. Timing belt #3 is coming soon.

Two piece fan shroud modification

Who is online