Grille Block advice....
 

Just fishing for a little bit of advice here. Jeeps run 2 cooling fans, one that is clutch driven (right side), and an aux. e-fan (left side). I'm looking at putting in a grille block, figured I would start with 40-60% first, and maybe go full if the temps don't climb too high. The advice question is this......Do I block off the right side, covering the clutch fan....or the left side, covering the aux fan (but also part of the air intake)??

Didja ever think of removing the clutch fan? Does it theoretically freewheel when the temperature is low enough?

RJ, I would suggest blocking the sides and leave your space in the center to begin. If your car does not run hot now, I would go to 75-80% to start. Watch your gauges. Some increase in temps may be a help to get into a more efficient FE range. That was the case for me.

I would also recommend sealing the grille block as well as you can. If not sealed well a lot of the air you think you are blocking gets thru creating tubulence as it does so. Get it right and you will see a gain.

Good luck. CO ZX2

All good points above.

Take note of what you're blocking the air flow from. Radiator and a/c condenser are usually mounted one in front of the other but if mounted side by side then you can decide your priorities.

Also remember you're doing two things with a grill block:
1) Improving aeridynamics by reducing turbulence in the engine bay, at the same time forcing the air to take a less harmful path over the hood or around the sides of the Jeep.
2) Reducing excessive engine cooling.

Not necessarily in that order.

Bill: I thought of removing the clutch fan, but the engine bay of a Cherokee gets unbelievably hot....some kind of design error, I guess. Going to leave the clutch fan in place until I get the e-fan replacement ready...then just do a direct swap.

CO ZX2: How would you recommend sealing the grille block?? I was going to zip-tie some coroplast to the outside for the beginning, make it easier to remove if my engine temps start jumping up. Maybe move it inside eventually, make it less noticeable.


Thanks for the help....let's keep the good ideas coming!!

RaccoonJoe

rj. I was looking in your garage but see no pic of your front end. Might be able to suggest something by seeing it.

CO ZX2,

Just imagine a battering ram with wide vertical slots. :)

[Sorry. The cynic in me is showing.]

Yea, that's about right. Then paint it a faded, oxidized dark purple......Maybe more like the front of a snowplow??

I'll get some photos up there soon....

*edit*
My photos are up in the photobucket account now....
https://i164.photobucket.com/albums/u...lie/img120.jpg
https://i164.photobucket.com/albums/u...lie/img115.jpg
https://i164.photobucket.com/albums/u...lie/img114.jpg
https://i164.photobucket.com/albums/u...lie/img113.jpg
https://i164.photobucket.com/albums/u...lie/img112.jpg

First is a shot from the passenger side of the Jeep, looking at the front clip. Then we have a shot of the air cleaner, and where it goes into the front clip. Finally, we've got some left and right, and full on frontal shots.....

Imagine a cross between an Element and a Volvo Wagon. :-)

Sealing grille block.
 

rj, I have my own grille opening completely covered. See it in my garage.

You have a nice flat surround on the outside of your grille to tape to. The coroplast should work for you. When you decide how much grille opening you need, I still would cover the entire grille then cut a crosswise slot an inch or so wide to line up with the centers of your fans. With a narrow slot, it is easy to add to or subtract with tape when needed. After my grille block was duct taped on I masked around the tape real tight and painted the tape and the block at the same time. Looks fairly decent.

Don't wreck your paint job.;) We all gotta start somewhere.

Good Luck. CO ZX2