158°F

[AncientCityJL]

158°F is what it takes to fry an egg.

I remember reading somewhere a guy was asking if the liner under our hoods is in place to stop the paint from burning or otherwise being ruined by the heat of the engine. Several forum members schooled him on the fact the liner is in fact a sound dampening device - as noted by FCA. As proof, they even submitted links to the part number and description (silencer pad) on Allmoparparts.com. People didn't believe the proof presented in black and white. And it got me thinking.

I know, so the egg, right? I was wondering with Florida being hot as hell, can you actually fry an egg on your hood. Well, it wasn't particularly hot today (remember we're only in February) but I decided to go out and see just how hot my hood was on a day when it was in the 80s. I hadn't driven anywhere so the temperature would be a good baseline. *I think now is a good time to note I still have my silencer pad installed. For now.

This first image is my hood at 141.8°F max temp.

This second image is interesting and it demonstrates the importance color plays in how hot your vehicle gets sitting in the sun. It's my wife's not JL - the one we shall not speak of here. Her black truck measured 147.6 °F max temp

Anyone else know what their temps are? Either running or not - cold or hot?

I'll take another measurement toolin' down the road as soon as my wife gets off work. Any bets? Colder/Hotter?

Sponsored

 

[Reinen]

It's 9 degrees with two feet of fresh snow so cooking an egg isn't in the cards right now.

But yeah, color will make the biggest difference. At least in UT. Because of the altitude the sun is 25% stronger/hotter than in Florida. It's why there are so many white vehicles in the SW desert and so few black vehicles. We're not boring, white is functional when it's 100+ and full sun.

My bet will be slightly cooler because you have airflow both above and below the hood while driving. But park the car in the sun with a hot engine and you'll see the hood temp skyrocket, especially the black one. I've had heat soak issues doing that when it's really hot and sunny. Weird codes, limp mode activated. Let the Jeep sit for 20 minutes with the hood open and all is well again.

 

[AncientCityJL]

It's 9 degrees with two feet of fresh snow so cooking an egg isn't in the cards right now.

But yeah, color will make the biggest difference. At least in UT. Because of the altitude the sun is 25% stronger/hotter than in Florida. It's why there are so many white vehicles in the SW desert and so few black vehicles. We're not boring, white is functional when it's 100+ and full sun.

My bet will be slightly cooler because you have airflow both above and below the hood while driving. But park the car in the sun with a hot engine and you'll see the hood temp skyrocket, especially the black one. I've had heat soak issues doing that when it's really hot and sunny. Weird codes, limp mode activated. Let the Jeep sit for 20 minutes with the hood open and all is well again.

Hmm. Interesting. I wonder if the silencer pad would serve as insulation in your case. I mean with it being 9°F. Probably not - because of the ice-cold airflow.

And I agree I think it'll be cooler while moving because of the airflow.

It'd be interesting to see the difference between my readings and yours in the summer.

 

[fat_head]

The science is settled. I will leave my pad in just so I don't have to listen to the sound of eggs frying on my hood.

 

[Reinen]

Hmm. Interesting. I wonder if the silencer pad would serve as insulation in your case. I mean with it being 9°F. Probably not - because of the ice-cold airflow.

And I agree I think it'll be cooler while moving because of the airflow.

It'd be interesting to see the difference between my readings and yours in the summer.

My conclusion during my heat soak incident was that the primary problem was that the engine was normal but hot and shedding heat, the sun on the hood was contributing a bit and there was no place for hot air to escape with the fans not running and hood closed. Absolutely everything under the hood was too hot to touch continuously. Air intake, fuse box, even the washer fluid container. All stuff that should not be that hot. Yet the coolant and oil temps were on the high end but in normal range. I don't think the hood liner made any difference there. I just had to open the hood and let all that heat escape. Mind you, this was shortly after a 15 minute stop with a hot engine in 108 degrees and full high altitude desert sun on an asphalt parking lot. It was hot out.

I opened the Rubi hood vents specifically to allow hot air can chimney out in this situation. It hasn't happened since but I haven't been in quite as hot environment since then. I strongly suspect that would resolve the heat soak problem though. It was painful to reach in and undo the hood latch with all the hot air trying to get out of the engine compartment.

But as far as the hood liner is concerned, I don't think there's any benefit to removing it.

 

[dragoneggs]

Where’s the egg? Someone needs to chime by summertime!

 

[aldo98229]

Out here color makes a big difference between the recovery team finding you in the snow ...and not finding diddly squat.

 

[dragoneggs]

Out here color makes a big difference between the recovery team finding you in the snow ...and not finding diddly squat.

Aldo, you cannot abandon that Jeep! Look where it has taken you!

Sponsored