[SuperDave1984]

OK my XJ gets really hot under the hood when wheeling. So since I am fairly creative and a redneck, I put the two together and fabricated a way to get the hot air out of there. It started with two fans I took out of an old server from work. They are about 4" in diameter and move quite a bit of air. Then I got some wooden serving bowls from Wal-Mart and got to fabricating. Here's the results. I srayed them with the spray-on bedliner for waterproofing, put a toggle switch on the dash and it works like a charm. I tried coating them with fiberglass resin but that worked on one and not on the other. Not really sure why. I put #10 screws through the scoops and countersunk the heads, then put a nut on the backside to keep it from turning. Then I put some bondo over the screw heads. Looks a tad ghetto, but if it keeps the engine cooler I don't care. I curved the holes upward to keep water out of the engine compartment. Total investment: <$20 and an afternoon's work. And as a bonus, I have an awesome windshield defroster now too.

Measure a dozen times, cut once.


Honest, these were $5 each.


A little work with the jigsaw and some sanding.


Kind of committed to the project now.





I sprayed the holes with bedliner too to help with rust.


Not too bad.






My son was impressed.

[Rollbar]

Looks good, good idea, what CFM do they put out/move, each. Did U scientifically position these to the hotest part under the hood or .............. Are these things water proof & what size fuse did U run for these fans.

[SuperDave1984]

Rollbar, on Aug 10 2008, 07:21 PM, said:

Looks good, good idea, what CFM do they put out/move, each. Did U scientifically position these to the hotest part under the hood or .............. Are these things water proof & what size fuse did U run for these fans.

I have no idea the CFM, but they move a lot of air. About like your typical 6" desk fan. I put them where I had clearance. Not exactly scientific, but there's not much room under there. One is right over the exhaust manifold and the other is right over the intake. No idea how waterproof they are and I used a 10A fuse.

[NonStop]

You might be a redneck if... you use serving dishes as hood scoops..

Seriously, I love this, you made use of what you had, and i know some fans of that style, they move plenty of air to evacuate a good amount of heat at stop lights and such. And those wooden dieshes are pretty tough. On the highway they may not keep up with the naturaly flow now that you have those holes but that is perfect.. The water proof aspect, I wonder how they will last considering the moisture free environment they where intended for.. However they are well made to begin with.. Keep us updated..
Again, awesome cheap trick..

[soflmuddin]

love it, except i didnt do it first. im the king of cheep rigs, and this is just that. i think the wood would hold up for years if it was coated thoroughly with paint. the electric motors i question as they were never designed for that harsh of an environment. im referring to the water run off it might see from the top of the hood. i know you can get these motors at radio shack. i would be interested in a repost in a year to see how the motors are doing. im gonna post this on another forum. thank for the idea!

[JeepDew]

well hopefully the termites dont get to it....

[SuperDave1984]

soflmuddin, on Aug 10 2008, 09:59 PM, said:

love it, except i didnt do it first. im the king of cheep rigs, and this is just that. i think the wood would hold up for years if it was coated thoroughly with paint. the electric motors i question as they were never designed for that harsh of an environment. im referring to the water run off it might see from the top of the hood. i know you can get these motors at radio shack. i would be interested in a repost in a year to see how the motors are doing. im gonna post this on another forum. thank for the idea!

I was concerned about the water run-off too, so I bent the lip of the holes for the fan up about 1/4" to help keep water flowing around the holes. I didn't think about if the scoop filled with waiter during a hard rain, but I am guessing it isn't a perfect fit against the hood and it will drain under the edge.

[JeepinIan]

Does the higher air pressure from the cowl interfere? I know that cowl scoops are used on street rods to get the cooler air, at higher pressure, into the engine. That air pressure may be fighting the fans you put in.

[SuperDave1984]

JeepinIan, on Aug 11 2008, 11:46 AM, said:

Does the higher air pressure from the cowl interfere? I know that cowl scoops are used on street rods to get the cooler air, at higher pressure, into the engine. That air pressure may be fighting the fans you put in.

Probably at highway speeds, but this if for off road where I rarely get over 10-15 MPH. One note of concern here however. I originally wanted to mount the fans to the firewall with ducts running out to the fenders. Would have looked cool, but the unibody would have been weakened (IMO) from a 4" hole in the side. Then I thought about just having them blow directly into the cowl area since it's open anyway. But I happened to think that isn't that where fresh air comes into the cabin? I am hoping that I don't get any CO inside from how I have it now. If I don't post after the next time I take it out, you'll know.

[NonStop]

You may want to get one of those cheapo remote thermometers, think they run like $20 at Radio Shack or less other places. then check underhood temps on and off.. Just make sure the Thermo goes up high enough.. I think it will work well enough though, probably even work a little without the fans, those are some decent size holes..

[SuperDave1984]

Yeah as I was cutting them out I was thinking "No going back now"

[SuperDave1984]

Upon further review, the bedliner has bubbled in a few spots. Maybe I will just go with a dozen coats of paint...

[NonStop]

That wood is very dense and has a wax or similar type product applied from the company, it may serve well to really rough up the finish (80 grit) and clean it well.. the bed liner is rough enough that the finish will still look good.
I would really perfer to see you clean and sand them then apply a few coats of a nice deep cherry finish.. Come on, you would be one of a kind then..

[SuperDave1984]

That's the thing, I sanded them before I sprayed them. Maybe there is an oil in the wood.

[NonStop]

Yup, that is how they get that sheen and the feel, just like rubbing with linseed oil or something.. Sucks for paint, but I still say go with something like a nice cherry finish.. There is no question that they have a great shape as a scoop especially with the nice shape of the cut out you made.

[WRider]

I really like what you did to the hood of your jeep...
My only concern is how long will the wood lasts through changing weather conditions....

[SuperDave1984]

I couldn't stand the bubbled paint, so scoop 2.0 has been created. This one is aluminum. A little body filler and some paint and VIOLA! I may paint it back though, not sure yet.

[TallJeep]

How are the fans working out ? Did they get wet yet?

[SuperDave1984]

Not yet. We haven't had rain in a LONG time. Looks like ya'll are getting plenty though. Hope everyone is safe down there.

[AlexP]

Very creative SuperDave! Very cool!! Check out this topic from another forum regarding the same issue.

http://go.jeep-xj.in...rRestrictor.htm

[JeepDew]

couldn't you use a snorkel to vent air out, turn the invent top backwards and not conect it to the air intake, wouldnt the pressure inside the engine bay from the air coming in from the front push the air out the snorkel, I guess we could call it the reverse snorkel...

[JeepinIan]

AlexP, on Aug 18 2008, 09:39 PM, said:

Very creative SuperDave! Very cool!! Check out this topic from another forum regarding the same issue.

http://go.jeep-xj.in...rRestrictor.htm

That;s a diferent issue. The coolant is going too fast through the block, not allowing the water to actually pick up the heat from it.

[JeepDew]

hey I also found this, little expensive but may work also....
http://www.techhoods...ds/Scoop-F1.htm

[SuperDave1984]

Looks nice, but it's also 4" tall. I don't think I want something that tall. Mine is just over 1.5" tall. Cost $0.

[NonStop]

Do to your MacGyver like creativity, a big I just gotta ask??? It almost looks like a baking tray or something.. What did you use this time?

[SuperDave1984]

Nonstop, on Aug 18 2008, 10:16 PM, said:

Do to your MacGyver like creativity, a big I just gotta ask??? It almost looks like a baking tray or something.. What did you use this time?

DING DING DING. I used a huge commercial baking pan. Yes, I'm a redneck.

[soflmuddin]

i like this guy.

[JeepDew]

I still think that a reverse snorkel would do the same......

[SuperDave1984]

I can see me making another one sometime soon. Make a mold out of Styrofoam and then lay fiberglass on there. I think I want one that goes further down the hood and has the hood depression the length of it. Hmmm...never satisfied...