Lifting the hood for cooling

[Black Dog]

I did this for my '85 4runner, except I used a $4 heater vent cover from Lowe's, sorta qhetto, but it works. I don't have cooling problems, but I did it to make sure there were no cooling problems while exploring DVNP during the summer.

Its ghetto, but its cool! (pardon the pun) Really if you think about it, if you are building an expedition rig and you are out on an expedition and have a problem you're probably absolutely in the middle of nowhere and have to improvise and do what you can with what you have.

 

[radar95zj]

These are the vents on my 5.9....

.

I really like that!! Gives me bad ideas

 

[CanuckMariner/Nomad]

....They DO NOT work to cool an engine that is running hot due to PROBLEMS!! ....So, the statement that water wetter does not work is a grossly misinformed statement. It just won't work for something it was not designed for....

As stated (you might want reread the post) "...I have heard about additives like Water Wetting, which with personal experience and testing, do nothing to control heating problems. Sounds kinda the same as you said, no?

 

[SWbySWesty]

Also note for water wetter...I'd probably only use it if I were doing somethign generating lots of heat like racing my motorcycle at the track or something, but for general use, I don't see the necessity.

I agree that if it's running hot, find the problem. But if it's not overheating yet, it's not a problem.

 

[4Rescue]

You can get a "Louver Cutter" at some hardware stores and just cut what you want into your hood. Maybe try something like the 5.9's or the vents on Toyota FJ40's hoods. Just a thought.

As someone else said, run a good water-pump on the 4.0L that is a known failure area on these motors and when it goes you're stuck...And x2 on the tranny cooler, that should be the first mod to an Expo XJ imo, as stated the tranny and motor have different ideas on ideal opperating temp. Seperating their cooling duties makes both happier.

Cheers

Dave

 

[BIGdaddy]

ok, so I run an aluminum radiator, and don't have any issues with overheating or running hot.

having just added a winch, I'll likely add Le baron or similar vents, in my hood in the next few weeks.

here's pics of other XJ owners installs of hood vents...

There are no reported issues with water from rain or offroading, and no issues with snow, mud, etc, either. In the winter the vents, if placed nearer to the windshield, do in fact act as defrosters by directing warm air towards the windshield.

 

[BIGdaddy]

By lifting the rear of the hood low vehicle speed cooling may well be enhanced, but high(er) vehicle speed cooling most likely will not. The base of the windshield becomes a high pressure area as vehicle speed increases. Opening the rear of the hood in these conditions can allow that high pressure air to enter the engine bay. While it is cooler, it tends to "dam" airflow through the engine bay - which means that it can reduce the airflow through the radiator.

Louvers in the middle of the hood will allow hot air to escape the engine bay during low speed operation. At higher speeds the middle of the hood is a low pressure area. Having the louvers in this area can actually cause the low pressure to pull more air through the engine bay. The downside to this is that the exiting hot air then is blown into the base of the windshield where most vehicles have their vent air intake.

The way to test where the high and low pressure regions are is to tape 1"-1.5" long sections of yarn in a grid onto the hood, and then go for a drive. Need only do one side as the other will nearly mirror it. The yarn will trail off in the direction of the airflow where it is high pressure, and will flap around randomly where it is low pressure.

The rivet-on louver panels are convenient, but expensive. Louvers punched around here run about $1.50 per louver. Try looking for a local street rod shop and ask them about louver punching. The black areas on this XJ's hood hide louvers punched by a mutual friend of mine and those two guys. (Yes the XJ towed that drowned 4rnnr out of there.)

anymore pics of that day?

Is that the water crossing on the way to the mojave rd.?

thats not SWR (mark)'s 4runner, is it?:Wow1:

Was the poor 4runner damaged at all? or able to be dried out..

 

[Black Dog]

There are no reported issues with water from rain or offroading, and no issues with snow, mud, etc, either. In the winter the vents, if placed nearer to the windshield, do in fact act as defrosters by directing warm air towards the windshield.

Thats kind of important for drivers in northern climes. In places like here its normal to have several feet of snow on the ground at any given moment during the winter, and that will usually land on your hood before you get a chance to scoop it off, not to mention water coming in while you are fording a creek or in a heavy rain fall. It really isn't that much moisture coming into your hood when you think about it, at least not enough to cause any real damage any way.

 

[DaJudge]

Before I installed Lebaron vents I could not touch my hood latch it was soo hot. The vents made a big difference in the underhood temps. They did however make my interior vents useless. The air on recirc works great but anything using the outside air is too hot. The air coming from the hood vents gets drawn into the intake. This is offset be the other benefit, the tranny tunnel is not as hot as it used to be. Instead of the engine bay heat being forced down and under the jeep, it escapes out of the hood. At highway speeds the vents do not do much as was already stated but they have made a big difference on the trail and around town.

Go-Jeep has some good write-ups on hood vents (http://jeep-xj.info/) scroll down to the Body Modifications section.

I also have no issues with water coming in the vents causing problems. I ran it through the carwash yesterday and even though I live in the desert we do get some serious rain storms occasionally.

Hope this helps!

Glen

 

[gasman]

couple o thoughts i dont like spacers ,, it looks like the hood dont fit.. but nobody has addressed the safety issue here.. what would happen in a collision .. could the hood become dislodged and come thru the windscreen?

 

[CanuckMariner/Nomad]

Wouldn't it be better to try to figure out why the engine bay gets hot in the first place? I agree with the safety issue and that you might have some insurance issues with an accident. When the rig was stock I am sure there were no heating issues, so why are there some now? What mods have made this happen? Before you go the louvre route or vents, and the lifting of the rear of the hood, one should try to find out why it is getting that hot in the first place. These mods are simply resolving a problem which left unchecked will result in more damage and maybe serious damage at that.

 

[Amauri]

Anyone tried or seen anything like this done on a jeep?

It's a fairly common mod on S2000's, here's a link: http://www.s2ki.com/forums/index.php?showtopic=324009&st=0
I've been wanting to try it, I think I might be able to pull it off with a steady hand and my dremel....

 

[Root Moose]

Hmm, never thought of that. I'd put it out of my mind because I think it is too "blingtastic" on an S2000. I'd do it on a Jeep though. In fact I really like that... probably will.

I was thinking about putting vents at the front outside corners like the euro-spec Orvis Cherokee. That'll let some heat out and the flow back across the hood should be diffused by the time the air hits the windshield root. Maybe it makes sense to make some kind of a deflector to control rain water so it doesn't go straight on the battery or ECM on the other side.

The other location I'm considering is above and behind the fan shroud. I'm not sure what that'll do to the flow in the engine bay though.

If you integrated "quick clip posts" into the mesh you could put blank out panels for every day driving or bad weather driving.

$0.02

 

[AFSOC]

Anyone tried or seen anything like this done on a jeep?

http://www.naxja.org/forum/showthread.php?t=1014094

I've seen a few similar to the S2000 example you've shown. The above link is to one of the first (of that type) XJ vent cuts I have seen documented. There are quite a few others that have taken inspiration for their own projects cropping up. I like the idea, lots of possibilities for shapes and placement.

 

[Waytec]

Thanks for all the input. I have been doing more research and talking to allot of people.
This is what I have found, engine over heating is not an issue, the cooling system is really good. The engine bay getting very hot is due to the engine and transmission being worked hard on the trail. my rad is cooling the engine but the heat instead of going down and out like at hwy speed it is just going up and in.
So for the climate I am in I would want hood lovers or lift the back of the hood. this allows the hot air at trail speeds to go up and out. but at hwy speeds it will have the air go around the vehicle as normal.
I good friend of mine that has been at this for longer than I have been on this earth and he designs oil field vehicles said hold off on doing anything. I just re-geared to 4:56 now I am crawling up and over stuff instead of giving a run at it. The engine and transmission are working less now. so I am going to wait and see what happens this summer.