Hood heat shield

[WILDHOBO]

In my case, I removed the heat shield so I could open up the Rubicon hood vents, in an attempt to remove some heat from the engine bay (to lower oil temps on the diesel). I'm not gonna sit here and bullshit anyone claiming it made a difference because I don't have any real proof and frankly I don't give a damn. Been running this way for about 2 years now in the Pacific Northwest and have had zero issues with water onto the engine or any evidence of paint degredation on the hood.

I can see the vent argument for sure. If I ever did it, I’d try to modify an insulator to just expose the vents. Then I think it would be pretty great. Even without data I’m sure yours runs cooler. How could it not?

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[kb5zcr]

Can I ask why you’d remove it? I’d expect paint failure eventually, is one of its purposes is to protect the exterior paint on the hood.

I haven't yet, but I did find that squirrels have been chewing on the foam insulation pieces up by the hood hinges. I pulled them out and was thinking about removing the entire hood insulation panel for the same reason. I haven't seen any signs of chewing on that so maybe it doesn't taste as good to the squirrels.

 

[fsm001]

I had a rodent problem, and they had a field day. Looking for a replacement heat shield for 2023 mojave. I know the cowell is different for the mojave so I assume the hood is also

Yhanks

Rodents are the worst under the hood. Check an online parts diagram to ensure you order the right shield for your trim.

 

[WILDHOBO]

Rodents are the worst under the hood. Check an online parts diagram to ensure you order the right shield for your trim.

Or just ask Benny @AllMoparParts.com. He’ll set you up. I want to replace mine just from 5 years of dirt and wear. It’s impregnated with dust.

 

[Sweetums]

I know this is an old post but I was just researching because I may remove my hood insulation and saw this.

Here is what AI says about the Volvo "fire blanket". I know AI isn't always right, but I believe it in this instance.

I asked AI if they used the hood insulation as some type of fire blanket.
Here is its answer.

Answer-
No, Volvo did not design or create the under-hood (bonnet) insulation primarily as a “fire blanket.” It is standard automotive sound-absorbing and thermal insulation (often called a “hood insulation pad,” “sound absorber,” or “insulation engine compartment” in Volvo parts catalogs). Its main purposes are reducing engine noise transmitted into the cabin and shielding the hood paint/structure from engine heat.0c885d
usparts.volvocars
Volvo’s official part descriptions and diagrams treat these pads (examples include part numbers like 31383344, 31298731, 30740133, 8641171, etc.) as acoustic/thermal components. Aftermarket replacements sometimes advertise “fire-resistant,” “flame-retardant,” or “fireproof” properties because many modern under-hood materials are self-extinguishing or heat-resistant by design (common industry practice to limit fire spread). This is secondary, not the reason Volvo fitted them.fc0668
Autohausaz
Related notes and context
Forum discussions and myths: Volvo owners sometimes call the pad a “hood blanket” and speculate it could act as a fire retardant. Others correctly note that a pad fixed to the underside of the hood cannot effectively smother an engine-bay fire (which is typically fed from below by oxygen and fuel/oil sources). Removing it mainly increases noise and under-hood heat.bb955f
Swedespeed
Research on under-hood liners in general: A 2000s study of various vehicles’ under-hood insulation found that some materials resist ignition well and that heat could theoretically melt mounting clips, allowing a liner to drop onto a fire. This was presented as a possible incidental benefit of fire-resistant designs, not evidence that any manufacturer (including Volvo) engineered the part specifically as a deployable fire blanket.09e16e
Mvfri
Older patent idea: A 1990s patent discusses impregnating engine-compartment sound-absorbing material (including under the bonnet) with expanding polymers that release fire-suppressant gases when heated. There is no clear public evidence this was implemented by Volvo as a standard “fire blanket” feature.9e7218
patents.google
Actual Volvo fire-blanket use: Volvo service centers (e.g., in Taiwan) have equipped with large external vehicle fire blankets (such as Bridgehill models sized for SUVs like the XC90). These are separate, heavy, purpose-built covers that two people pull over an entire burning vehicle (especially relevant for EV battery fires) to starve oxygen and contain the fire until professionals arrive. They are not related to the factory under-hood insulation pad.376f6f
YouTube
In short, the underside-of-hood pad is ordinary NVH (noise/vibration/harshness) and heat insulation that happens to use materials with some flame-retardant characteristics in many cars, including Volvos. It was not created or marketed by Volvo as a fire blanket.

Well, one thing I see wrong about the AI answer is that car-sized fire blankets for EV fires do not deprive the fire of oxygen. Lithium-ion batteries contain all the ingredients for fire internally, including oxidization; this is exactly why they are so hard to extinguish. The EV fire blankets are there to prevent the fire from spreading while water is pumped to try to cool the temperature. This isn't a necessary tool for ICE vehicles, which rely of oxygen in the air to burn, burn more slowly, and burn at significantly lower temperatures. EV fires burn at about 5,000 degrees, while ICE vehicle fires are typically around 1,500 degrees (F). Although ICE vehicles catch fire more often, the dangers of EV fires, including heat and tendency to self-reignite, make them particularly dangerous for firefighters.

 

[WILDHOBO]

Well, one thing I see wrong about the AI answer is that car-sized fire blankets for EV fires do not deprive the fire of oxygen. Lithium-ion batteries contain all the ingredients for fire internally, including oxidization; this is exactly why they are so hard to extinguish. The EV fire blankets are there to prevent the fire from spreading while water is pumped to try to cool the temperature. This isn't a necessary tool for ICE vehicles, which rely of oxygen in the air to burn, burn more slowly, and burn at significantly lower temperatures. EV fires burn at about 5,000 degrees, while ICE vehicle fires are typically around 1,500 degrees (F). Although ICE vehicles catch fire more often, the dangers of EV fires, including heat and tendency to self-reignite, make them particularly dangerous for firefighters.

Yep. They don’t burn often like the internet conspiracies say, but if one is on fire, just get clear. Don’t get me wrong, it doesn’t make me nervous to own one. We have one bev and one phev. But it’s important knowledge to have. Know what your car is, and how to maintain it. And how to respond to an unlikely thing like a fire.

 

[DanJT]

I can see the vent argument for sure. If I ever did it, I’d try to modify an insulator to just expose the vents. Then I think it would be pretty great. Even without data I’m sure yours runs cooler. How could it not?

My S&B hood vent allowed me to cut out the vents and retain the padding.

 

[WILDHOBO]

My S&B hood vent allowed me to cut out the vents and retain the padding.

Those look fantastic. Do they have a manual closure for torrential rain or winter?

 

[DanJT]

They do have plugs for the opening when needed

 

[WILDHOBO]

They do have plugs for the opening when needed

Pretty cool. Those might be on my list someday.

 

[DanJT]

By the way, they have wells that direct the water to the side just like the factory false vents do!

 

[WILDHOBO]

By the way, they have wells that direct the water to the side just like the factory false vents do!

Well designed. Nice.

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