Electric Fans Mounted in Hood

[teachersnake]

Hey everybody, with summer here I imagine there are quite a few of us who are starting to think more and more about overheating. I've got a 98 XJ, which are known to run warm, and I'm always looking for ways to keep her cool. This got my thinking about something that I saw once in Qatar (where I spent a bunch of time as a kid).

There was an older Land Rover (110, maybe?) with a pair of electric fans installed in the hood, presumably to blow hot air out and away from the engine compartment. I couldn't find anything like this on the interwebs, so I was wondering if any of you have tried this or even heard of it being done before. Most 4x4s in the Mideast have heavy duty cooling systems installed from the factory, so maybe this is why I've never seen one stateside?

I know that it wouldn't have a huge effect on reducing the temp of my coolant, but it'd be nice to lower those under hood temps for the sake of plastic components, intake temp, etc.

 

[Superu]

I like the idea.

Would you expect it to be partially covered by a scoop to keep rain from pouring in when not in use?

Thermostatically controlled or toggle switch or both?

Driven off vehicle's electrical or solar powered like cabin vents for boats?

 

[bobDog]

On the site http://www.xxxpedition.com If you root around Sven's US Trips you find several photos of his and someone elses XJ w/ exactly what you are talking about. This is a great site w/ lots of great trips.
You'll also find a build thread here on Expedition Portal labeled "Project XXX " about his new Jeep.
:smiley_drive:

 

[R_Lefebvre]

What indications are there that you have a real problem? You're right, it won't have much of any effect on coolant temps. I also don't think it will have much of an effect on intake temps, unless you're drawing underhood air which you shouldn't be anyway. Are you really having a problem with underhood plastic melting?

Perhaps a non-powered vent cut in the hood would be enough to give you some benefit without the complexity of a fan. I cut a hole in the hood of my Focus because it's making twice as much power as stock, and I use it on track days where I have actually melted plastic under the hood.

You can see the heat coming out when the car is stopped, even without a fan.

 

[Pskhaat]

I installed a JDM pusher fan that after-runs in my FZJ80 and this has helped re-start temps, anecdotal but pretty clear that AC is colder and much more heat movement from hood slots.

Older LCs had carb fans which (again) appeared to help a lot and I've considered installing an after-run blower as well, getting heat out of the compartment after stopped has helped a lot with round-town AC.

 

[teachersnake]

@ Superu: I was thinking about some type of louvres that would be pushed open when i turned the fan on but would otherwise remain closed. Not sure where I could find something like this or if I'd have to rig one up myself.

@bobdog: thanks for the site reference, I'll scout around and see if I can find a picture to post for this thread.

@ R Lefebvre: No, I haven't had any problems yet with plastic melting, and to tell the truth I don't really expect to have any. But the quality of Jeep's plastic is poor enough as it is, and a black hood really helps heat things up even before the engine is warm. I'll be relocating to the 4 corners area in a while and want to make the XJ run as cool as possible before it becomes a problem.

 

[teachersnake]

Here's a fella from naxja that did it:
http://www.naxja.org/forum/showthread.php?t=92583&highlight=hood+heater+core

Apparently it worked pretty good for him. I'll let you all know what I decide and how it works out.

 

[truck mechanic]

old gas powered line trucks had just that set up, the hood mounted fans would go on by a temp switch in the block, I dont know if they were done at the factory or if someone like mabell put them on. The trucks did stay cool however.
Paul

 

[FishPOET]

Have you considered putting an oil cooler in the hood.

 

[Christian]

Have you considered putting an oil cooler in the hood.

Whoa! That's a neat looking unit, might be perfect for my water-to-air intercooler, where's that from?
(btw sorry for the highjack...)

 

[teachersnake]

Fishpoet that's excellent. That's exactly what I was going to build. I'd also like to know your source...

 

[KG6BWS]

http://www.xxxpedition.com/ShortTrips/2005-Anza/Gallery/IMG_5238.jpg
ive thought of doing something similar on my hood for engine oil and trans fluid coolers without putting any more restriction on the radiator.

 

[Stumpalump]

I also have a 98 XJ and like all XJ's the cooling is poor. The problem with them is the radiator. They don't last and even a two year old one is not as good as new. They are just over 100 bucks at advanced auto so I would do that first.
I added Chrysler La baron turbo hood vents to my hood and relieved the cowl by spacing the hood and removing the cowl gasket. I moved the hood as far forward as I could, put spacers under the hood hinges and beat the strip that held the gasket down. Next I leaned down hard on the hood corners to bow them down so it doesn't look jacked up. A ton of air rushes thru now. This mod is best for crawling and not for the interstate. On the interstate low pressure under the vehicle pulls air thru better if it's all sealed up.
The factory uses two fans and one is electric. You can put a switch on your A/C compressor to keep it off then by switching it onto recirculate air the fan will run but not the A/C compressor. You will suck hot air inside if you mod your hood so recirculate will run the fan and not pull hot air inside your cabin.

 

[Christian]

Fishpoet that's excellent. That's exactly what I was going to build. I'd also like to know your source...

i found it, it's a Flex-a-lite unit, here you go:
http://www.flex-a-lite.com/auto/html/oil-coolers.html

 

[dieselcruiserhead]

I'm pretty sure cooling would be minimally changed with those cooling fans. Ultimately just fix or beef up the regular, real system otherwise it will be expensive and never be fixed... I hope it helps...