Different Strokes for Different Folks JK Wrangler Hood Vent

[mmaattppoo]

After pining over the many options available for ready made and DIY hood vents for my JK I decided to go off on my own and install a single two-way hingless vent on the left side of my hood.

The idea for using a two-way hingless vent came from a XJ owner on another forum who installed a pair of vents on the hood of his XJ. I only installed 1 vent due to clearance issues under the hood. Two vents would have been better but one is better than none. I didn't want to cut any of the structural reinforcing to install a vent.

After a quick rip on the road following the install, including being stuck in a paving construction zone for 20 minutes, I could see heat shimmer coming from the vent side and little to none on the opposite side. Between the visible heat shimmer and feeling the heat pouring out of the vent when I parked and placed my hand over the vent I'll take that as the vent doing something.

Note: I run an engine driven fan in addition to the standard electric fan so there is a constant large volume of forced air being sucked into and blown over/through the engine bay..more when the thermal fan clutch locks up above 150°F (engine bay temp). This single vent gives a portion of the hot air a place to go...the rest vents out under the vehicle and through the front fender wells.

Here are a few photos taken during the installation...the first cut was a little nerve racking but in the end it all worked out.

 

[Dan Grec]

Very nice! It looks really clean and matches your grill nicely.

I have no doubt it's doing a lot - the engine bay of my 2007 JKU is always roasting when I stop driving.

How does the vent open? i.e. does it automatically close and open with heat, or you do manually open it and it then stays open until you manually close it?

-Dan

 

[mmaattppoo]

Thanks grecy. I was pretty nervous about cutting my perfectly good hood, but it worked out for the best.

These two-way hingeless vents are manually actuated. Heat sensing like greenhouse skylight vents would be sweet but space constraints put a crimp in that.

There's a handle and a series of detents that allow the vent to open in 3 steps in two directions (inboard/outboard in my case). Here's a picture (not mine) that shows the details obscured by my hood:

Due to clearance issues with the ABS module/tubing and the PCM I cut off the tubular handle with no ill effect to the operation of the vent.

 

[mr2kxj]

When I was a kid in the 90's, our school bus used these vents on the escape hatches in the roof.

 

[Mitch502]

I like it. Subtle and useful

 

[bluehash]

I love it. Ingenious!
Where did you get the vent from?

 

[mmaattppoo]

I love it. Ingenious!
Where did you get the vent from?

Mill Supply. They're an online vendor of delivery van and truck parts. I'm sure there are many other sources for these vents but that's where I ordered mine from.

 

[NOMADIC_LJ]

That does looks really clean. I like actual functioning ideas like these.

 

[mmaattppoo]

That does looks really clean. I like actual functioning ideas like these.

Thanks NOMADIC_LJ. The old adage of measure twice cut once was replaced with measure about 10 times cut once.

I too like functional modifications. Function over form is my driving M.O.

Between this forum and the wealth of several other forums, and YouTube, this install went quite well.

I Iearned a few new tricks to boot. In particular the use of rare earth magnets to aid in locating points through the hood from inside to outside and using right/left cutting tin snips to do a job I was convinced would require a cutoff wheel or jigsaw.

Owning A Jeep is kinda like having your own trades school on wheels. It never ceases to provide a lesson or two.

 

[Dan Grec]

Do you have a photo that shows your entire grill / front of hood?

I'm assuming that's some kind of beadliner? I think it looks amazing and I'd really like to see the whole thing.

Thanks,
-Dan

 

[mmaattppoo]

Do you have a photo that shows your entire grill / front of hood?

I'm assuming that's some kind of beadliner? I think it looks amazing and I'd really like to see the whole thing.

Thanks,
-Dan

Sure do...

I used Raptor Liner applied using the recommended shutz gun and about 55-60 psi at ~4-5 cfm to get the desired pebbling texture (higher pressures result in a finer texture). I shot the inside of the tailgate, bottom of the door sills, the front 2 inches of the hood/fender, and grill to make the most of 1 of the four bottles of Raptor Liner. Here are a few photos of the process:

A few comments regarding the application of Raptor Liner, and any other bed liner:

1) prepping (sanding/removing dust/degreasing) and masking the area to be sprayed is essential. This single step should take at least 2/3 of the overall time to complete the application of Liner...esp the sanding and decreasing part. Have all areas prepped before you fire up the compressor and start spraying.

2) only apply the liner when it's warm and dry. Trying to apply Liner at the lower limits of its application temp is a good way to end up with lousy results due to incomplete/ineffective flashing of the volatiles from the liner mix amongst other factors.

3) give the Liner time to setup and off-gas. Insufficient setup time is the second most common way people screwup the application of liner. It's tack free about an hour and completely setup in about 24 hours...more time is better.

This was another function over form mod as the primary reason applying Raptor Liner was to prevent chips / dents to the leading edge of the hood/grill and to cover up several scratches to the lower door sills and inside of the tailgate. This mod just happens to also look pretty good too.

For the hood vent I used Rustoleum Truck Bed Liner instead of Raptor Liner. The Rustoleum Liner isn't quite as robust as Raptor Liner so it's best used where it's not going to see a lot of wear. We'll have to wait and see if the front left portion of my hood is exposed to sufficient amounts of debris to wear the liner away.

Hope this is what you're looking for. Enjoy!

 

[oscar the grouch]

you have an engine driven fan on a JK and electrical fans?

 

[mmaattppoo]

Sure do. I don't have any good photos of the install...but here's the source I used as inspiration for making this mod:

http://www.jeepforum.com/forum/f96/oem-mechanical-fan-retrofit-1378143/

There are several photos of the parts and lots of detail (e.g. part numbers) in the post at the link above.

 

[oscar the grouch]

must get a lot hotter in canada these days than i remember. I cant imagine the little port hole you cut lets a lot out.

I have one of those large hole cut louvers on mine in the south of the us where ambient temperatures are regularly in the 110s and have never thought i needed additional fans....

the louver is nice because it lets the heat go up instead of to the sides. you can actually stand next to the hood without roasting. Its very noticeable in the summer when wheeling with friends that don't have one. I applaud your thinking outside the box but I will be the one that dislikes the implementation on this one? letting some air out over the powersteering pump has little function and even less if you have to get out and open the hood to open the vent.


Personally something thats open all the time has more function and since clerance is an issue on the passenger side a set of louvers from genright might fit the bill and allow some of that hot air to escape over the engine intake.
http://www.genright.com/ProductInfo.aspx?productid=LVR1006

 

[mmaattppoo]

Thanks for the feedback Oscar the Grouch.

Your forgetting about our famous "north of the boarder" winters and the copious quantities of rain...mixed with salty road mist when driving British Columbia's mountain passes...and our 40°C (104°F) summers in the interior of the province. We get a little bit of everything when it comes to weather and climate.

I looked at louvers and felt that I needed to try something different, but more importantly, I'm not keen on the complete exposure of the engine bay to the elements mentioned above.

The ability to close the vent when parked in the pouring rain and when driving in the winter when I don't need ventilation is one of the main things that attracted me to the two-way hingeless style vents.

Agreed on the point about limited effectiveness...if I were relying on passive ventilation alone. However, in combination with the positive pressure and massive air flow from the mechanical fan this vent allows an appreciable amount of air to be forced out and up with the rest flowing out through the fender well and under the vehicle. While not likely to be as free flowing as a set of louvers this vent meets my needs difficult as it may be to qualify the results with actual underhood engine bay temperatures (not intake temps). My snorkel takes care of reducing intake air temperatures so the intake temp isn't a reliable means for my application in quantifying the effectiveness of any efforts to cool the engine bay.

I'm curious about actual underhood temperatures. Do you have any underhood temp measurements before and after your hood louvers? I've read on other forums people claiming temperatures in excess of 300°F! Now that's hot. At those temperatures JK owners should baking cookies and cakes while driving during their summer adventures.

P.S. Point of clarification regarding JK anatomy...the power steering pump for my 2010 JKU's 3.8L V6 is attached to the passenger side of engine The ECM and ABS pump/module is located near my vent. Hence my need to have a vent that can be closed when not needed.