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Hood vents, scoops etc. Heat extraction

Weekender

NAXJA Forum User
Location
Memphis
Our newly acquired '01 XJ is black and on a warm day we did have the vaporized fuel in the hot rail idle issue.

Summer here is brutal so I'm looking for options for scoops or vents on the low budget side. I've seen the spacer / stacked washer approach to raise the rear of the hood and wonder if that's effective.

On the next to that cheapest approach are the stick-on cosmetic hood scoops. If they were turned with the opening to the rear and suitably large holes drilled through the hood beneath them, might that work?

Can always get another hood from the junkyard.

Weekender
 
A very popular option that is generally affordable are lebaron hood vents.
 
I went with the Lebaron vents on mine. They helped, but I still heat soak if I shut down while running trails.
 
Hood vents, and an e-fan timer for cooling after shutdown. LeBaron and Pontiac Sunbird vents are somewhat common, ZJ 5.9 vents are less common.


My functional hood vents were donated by a Pontiac Sunbird.

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Hood vents, and an e-fan timer for cooling after shutdown. LeBaron and Pontiac Sunbird vents are somewhat common, ZJ 5.9 vents are less common.

Yeah but 5.9 vents are so much cooler. I don't seem to have heatsoak issues with my '00. I did have surface rust issues on the hood and roof. Figured since the hood had to be done anyway I did it just for the look. Can't post a picture of mine but you can see it here. Post # 84139

http://www.jeepforum.com/forum/f177...j-mj-today-566549/index5610.html#post36316153
 
Lookup the 1" rear hood spacers. They go on the hinges and raise the rear of the hood almost like a cowl. Independent tests shows a 20* temp drop.

Got mine off ebay for $15. 5 min install
 
I use the Napier hood louvers. They work well but anything that allows hot air to escape will reduce heat soak, especially over stock.

Sent from my SM-G930V using Tapatalk
 
Thanks for all the responses! Going to the U-pullit yard this weekend looking for vents. If I don't find anything I think the Napier vents will be the choice.

Weekender.
 
All 2001 US XJs have the dual mini-cats, most 2000s do not, unless California models. There is a big difference between having mini-cats and not having them.
https://www.cherokeeforum.com/attac...275237-codes-po138-po141-2000_2001exhaust.jpg
The mini-cats throw a huge amount of heat into the the intake manifold and engine bay. If you have the mini-cats, you most likely will have the heat soak problem in warm weather.
It's really a problem when wheeling at slow speeds.
It happens when a hot engine is shut off for just a few minutes. Wait twenty minutes or longer and it's not a problem.

Over the last 15 years, I have tried all the suggested fixes for this problem.
The fuel injectors and fuel pump hold pressure for longer than the Factory specs.
The fuel injectors have been wrapped, a TJ manifold heat shield (DEI kit) installed, the bottom of the intake manifold has been insulated, hood vents have been added and a adjustable fan timer installed, for use in warm weather when the engine is shut down.
While each added thing has helped some, the only absolute cure has been to use the fan timer, set to run for three minutes, after the engine is shut down.
Forcing the mini-cat's heat out with the electric fan prevents the hot soak problem.
 
Fan timer sounds like a must do for 2001s then. Another question, but I suspect I know the answer. I've seen under engine shields sold for the xj to keep water, mud, etc., off the belt and accessories. I suspect most XJs run without them as they're vulnerable to being torn off.

Do they make a difference in cooling, particularly when the electric fan is used to force heat through hood vents when stopped or slow running?

Great suggestions, much appreciated. Not to look for the fan timer mod wiring.

Weekender.
 
any benefit to wrapping the exhaust manifold? sits right under the injector rail. although it may still let heat soak up the rail, seems like it would keep things cooler while it was running. anyone ever tried it?

I need a new exhaust shield and need to wrap my injector rail for sure
 
any benefit to wrapping the exhaust manifold? sits right under the injector rail. although it may still let heat soak up the rail, seems like it would keep things cooler while it was running. anyone ever tried it?

I need a new exhaust shield and need to wrap my injector rail for sure

Can't speak for every manufacturer, but Banks will void the warranty if you use the wrap!
 
Can't speak for every manufacturer, but Banks will void the warranty if you use the wrap!

I doubt anyone is going to warranty my stock exhaust manifold from 1998!

so you're saying it keeps too much heat in that it will compromise the welds and structure?
 
I doubt anyone is going to warranty my stock exhaust manifold from 1998!

so you're saying it keeps too much heat in that it will compromise the welds and structure?

I think generally it can lead to faster corrosion/rust of the header itself. Think it would help but at the cost of shorter header life.
 
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