Hood Vents - JLU/JL Rubicon functional or only decorative?

JLUin818

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Jeepinformant pulls the hood vents off a Rubicon and inspects them thoroughly. Look fake to me but you be the judge.

"functionable". lol

that hole is purely to keep water from standing in that fake hood vent. they must not have felt venting was needed. easy enough to modify it to make it functional though. will the jeep actually benefit from more heat extraction? jeep must not have found that to be the case through extensive their testing.





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TheWingman

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"functionable". lol

that hole is purely to keep water from standing in that fake hood vent. they must not have felt venting was needed. easy enough to modify it to make it functional though. will the jeep actually benefit from more heat extraction? jeep must not have found that to be the case through extensive their testing.
Opening them may actually decrease heat extraction efficiency by creating an "air short" between the hood vents and the side vents. Instead of forcing the air through the front grill opening across the cooling system and engine block and then out the bottom and side vents. This may have indeed been the findings of the engineering group.
 

JLUin818

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Opening them may actually decrease heat extraction efficiency by creating an "air short" between the hood vents and the side vents. Instead of forcing the air through the front grill opening across the cooling system and engine block and then out the bottom and side vents. This may have indeed been the findings of the engineering group.
true. FCA spent millions in R&D on these things. keeping fuel economy and durability in mind the whole time.
 

allieboy

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There’s a thread here somewhere where someone poured water in them. Supposedly drained towards the back.
Any water going in those vents will end up in New Jersey
 

Patinito

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So, in conclusion, these vents are indeed non-functional for any benefit other than looks?
 

BillG

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The metal of the drain pan is thinner than what the solid hood would be, so some heat might escape there, but it’s not exactly air flow.
 

Slowpoke

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The fake hood vents are just pertties.
Totally eye candy.
 

Onyx Dragon

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Well, I guess we'll have to talk to the first RUBY owners that experience HEAVY RAINS--

Maybe there's no problem--or ??

JIMBO
I owned a 2001 Grand Prix and I purchased an aftermarket hood with the ram air up front and heat extractor vents in the back. The water coming down didn't do anything to the engine other than get it a little wet. It pretty much hit the engine cover and rolled off onto the ground.

That's probably the same thing that occurs here.

Plus, with this type of vehicle, I would imagine a little water isn't going to hurt it.
 

cbrenthus

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my 13 mustang gt had functional hood vents from the factory, no issues in the rain. My motorcycles have all spent plenty of time in the rain as well. Water doesn't hurt engines as long as there isn't an underlying issue, or as long as you don't submerse the A/C. Of course, the only issue I ever had with an engine getting wet was when I hosed off the engine of my '07 JKU and the cooling fan fried.
 

TheWingman

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my 13 mustang gt had functional hood vents from the factory, no issues in the rain. My motorcycles have all spent plenty of time in the rain as well. Water doesn't hurt engines as long as there isn't an underlying issue, or as long as you don't submerse the A/C. Of course, the only issue I ever had with an engine getting wet was when I hosed off the engine of my '07 JKU and the cooling fan fried.
Motorcycle electrical systems are designed for the rain. Direct water exposure to any electrical connection not designed for it will cause problems. The JL has many connections above the 30” line that are not designed to be exposed to water.
 

NathanG

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Being decorative has function. I reject the premise of your question.
 

cbrenthus

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Motorcycle electrical systems are designed for the rain. Direct water exposure to any electrical connection not designed for it will cause problems. The JL has many connections above the 30” line that are not designed to be exposed to water.
Having worked on electrical systems of both cars and bikes, I haven't noticed much of a difference. And I've hosed off many engine bays and never had an issue (except for my '07 JK lol!). If the JL has electrical under the hood that couldn't handle a little rainwater spray from open hood vents, that's not OK. I'm not saying it should be able to be submerged up to the windshield, I'm just saying that if a '13 mustang (that is not designed to ever go off road or ford water crossings) could have open hood vents without issues, then a Jeep should be able to as well. ;)
 

DerekPB

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Few newbie thaughts / points many likely agree with... Or not.

1) Many JLs have been running without any additional venting for more than a year but time may tell.

2) Rubicon vents... As they stand from factory are just decorative and to me thats BS. Make it functional or has no reason to be there :headbang:.

3) the factory vent, in some areas of the world, will have the drain hole systen clog up... And just cause problems for no real benifits.

4) I'm sure removing the bottom of the vent (and insulation) helps venting. Will it disrupt the "designed" cooling flow? Likely but its likely overcome by the additional venting.

5) I'm sure with removing the bottom will allow water in. Some isn't bad but I think it does matter over time and dependant on the climate your in (water/snow/ice/etc). I'm intrested to see comments in my area (North East / Great Lakes) after time / winter.

6) Has anyone done more a detailed modification such as cutting slots / holes in the side and modified to allow venting but keep the insulation under the drain to allow intended flow? It should improve some I would think.

At this point I'm going to wait till after this winter and see unless I have some heat issues or someone comes up with a insert mod.
 

viper88

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If you want more cooling, start with changing your grill/mesh to what is being used on the Gladiator.
I would be surprised if engineers overlooked a hack for a hood vent for better thermo efficiency. You are 100% correct. The Gladiator has enlarged grill mesh for more efficient thermal efficiency. Here is a great article on how much work engineers do to get the max cooling capacity. It does not look like the engineers left anything on the table after reading the article.


https://jalopnik.com/the-engineering-behind-the-jeep-gladiators-tow-rating-1833657453
 
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