TheSamba.com :: View topic - Engine cover re-insulation project- fire in mind

Sun Aug 18, 2019 6:12 am

So, after touching a lighter to a piece of factory lid foam insulation, and watching it catch fire and burn on its own in less than a second, I decided to try something else.

I had seen the link to a product on another thread, and looked into it.
The supplier said that particular product (a PET coated fiberglass) had poor flame contact resistance.
I was pointed towards this product:
Aluminum Foil Coated High Temperature & Radiant Heat Reflective
Fabric / Cloth: MIL Spec & Standard
300°F / 149°C DeltaGlass™ Continuous Standard Grade and 500°F / 260°C
Continuous (600°F / 315°C Intermittent) High Temperature Grade

https://www.abthermal.com/pdffiles/F/F-FG-AL-Fabri...ective.pdf

I also was pointed towards this:
http://www.firesleeveandtape.com/AB-Thermal-catalog-IM-FG-NEEDLED.pdf

To be used as sound insulation, and further heat resistance. I used the 1/2 in material.

My dilemma was how to attach it to the lid.
I didn't think adhesives were going to be a good option, so looked for something else.
I settled on these:
https://www.belmetric.com/metal-hardware-c-12_128_130/d10937-vw-retainer-p-5827.html

And 16mm truss head sheet metal screws

The sound insulation material handled very nicely- cut cleanly with a razor, and held its shape well.

I draped the second fabric over the top, then drilled holes through the whole assembly for the sheet metal screws.
The retainers just caught the 16 mm screws after squishing the sandwich some.

I left the fiberglass fabric long, and used a high temp (wurth) spray adhesive to secure the edges to the flange of the lid. As can be seen, I simply covered right over the rubber seal. I figured this helped reduce the rubber seal as a fire pass through.
Time will tell if this was a good option!

It still sits in place just fine, and the latches close as before.

I was concerned from the beginning about the thermal pass through of the screws, but tried it anyway.
Turns out I was right to worry!
First drive resulted in the screw heads on the top side being very hot!
I went back and covered the retainers with another product I had that was similar (fiberglass with foil cover) but had adhesive already applied to it.

Before I did this, I touched the tips of all the screws with a disc grinder to take the sharp off.

This significantly reduced the temp of the screw heads, but they are still quite warm.

Overall, the experiment worked out pretty good, though I do think there could be a better way to adhere the materials to the lid. But, I'm sure my lid is way more fire-proof than it was.

Sun Aug 18, 2019 8:12 am

That's a lot of work for a fireproof engine cover. Why not work on preventing a fire altogether (fuel lines, etc)?

Sun Aug 18, 2019 8:16 am

Good job. Time well spent.

Since your thread title is good for searches let me ad a link to this material I also came across:
https://www.thesamba.com/vw/forum/viewtopic.php?t=722193&start=40

Question: How much weight did it add the engine cover?

Sun Aug 18, 2019 9:47 am

That’s some good info, which I’ll use as I enjoy the privilege of redoing my half-assed hatch soundproofing job. As a cautionary note, I strongly suggest folks don’t use the HF padding like I did. I recently was welding in rust repair panels and used the stuff as a kneeling pad. It ended up looking like the craters on the moon from all the welding splatter.

Works fine as a sound deadener, but won’t cut it in a fire.

Sun Aug 18, 2019 11:46 am

Corwyn wrote: That's a lot of work for a fireproof engine cover. Why not work on preventing a fire altogether (fuel lines, etc)?

That's all new - everything, every last bit.

I don't believe 2 hours in the shop is significant, particularly when I don't believe in "altogether"

Sun Aug 18, 2019 11:50 am

Steve M. wrote: Good job. Time well spent.

Since your thread title is good for searches let me ad a link to this material I also came across:
https://www.thesamba.com/vw/forum/viewtopic.php?t=722193&start=40

Question: How much weight did it add the engine cover?

Whole lid weights 16 lbs - not sure what it did before.

Sun Aug 18, 2019 1:55 pm

nmerrillthere's def'n something to be said for protecting that foam from a fire.
A simple task that increases the amount of time you have to fight a fire, is time well spent.

You got me thinking about a thin sheet of aluminum.
It wouldn't be sealed, but mostly covered.

0.025" Aluminum Sheet 5052-H32 - Part #: 7124
24.0" X 48.0" - $20.54 ea + shipping (or will-call here in Seattle)
https://www.onlinemetals.com/en/buy/aluminum-sheet

I'd want the cover to be easy to use the rest of the time I dive under it (ie mostly "unchanged).
And being a Vanagon, thats kinda often.
.025*23.25*40.5*.1====> 2.3 lbs of aluminum added to the plastic cover.
Not sure how to attach it yet....

nmerrill I see you really sealed yours against the licking flames.
And it's "sound absorbant" whereas an aluminum might be noisy.
But it IS outside the van, and the foam remains.

Sun Aug 18, 2019 2:20 pm

Bostigs have an aluminum heat shield with hooks inserted into the (apparently highly flammable) foam:

As for the heat transfer through the screws, how about epoxying some studs to the underside of the lid which would poke through the fabrics and then attach the fasteners?

Sun Aug 18, 2019 2:28 pm

Yikes!!! As long as I had my cover off I thought I'd do a burn test. These theee photos may have been taken w/in one second. Flame and toxic smoke ensued.

Looks like we always have fire starter for the next camp out. :shock:

Sun Aug 18, 2019 3:18 pm

What Corwyn is recommending is reasonable. To advance the Vanagon to be as "fire-safe" as the 99.9% of other cars on the road, is the higher goal than minimizing the fuels (the foam etc).

I would LOVE to be so confident to feel no need to minimize engine compartment combustibles.

Sun Aug 18, 2019 5:12 pm

Sodo, I thought about something similar- and I think that would be a pretty good solution.
I couldn't go this route myself since I had already removed my foam!
Obviously, this does leave the rubber gasket exposed though.
Something else could be done to help there I'm sure

Sun Aug 18, 2019 5:24 pm

I strongly suspect the dimpled surface of the foam contributes to the sound-deadening qualities, so a hard smooth surface might just turn the space into an echo-chamber.

Sun Aug 18, 2019 5:26 pm

There are about 171,000 highway vehicle fires per year which account to 13% of all fires the FDs respond to. Mechanical and electrical failure account for 65% of highway vehicle fires.

According to FEMA..,
https://www.usfa.fema.gov/downloads/pdf/statistics/v19i2.pdf

While Vanagons certainly burn, there are plenty of Honda's and Toyota's on an image search in Google.

https://www.google.com/search?q=highway+vehicle+fi...mp;bih=549

I agree that prevention/reduction is important and it seems that removing this flammable foam is a reasonable tactic.

A few weeks ago I was stopped at a stop light on my 42 year old motorcycle and white smoke started billowing out from behind the fairing. Fortunately, there's not a lot that's quickly flammable so I was able to yank on the harness and eliminate the short to calm it down. Had the foam been there... :shock:

Fire bad.

Sun Aug 18, 2019 5:27 pm

jimf909 wrote: There are about 171,000 highway vehicle fires per year which account to 13% of all fires the FDs respond to. Mechanical and electrical failure account for 65% of highway vehicle fires.

According to FEMA..,
https://www.usfa.fema.gov/downloads/pdf/statistics/v19i2.pdf

While Vanagons certainly burn, there are plenty of Honda's and Toyota's on an image search in Google.

https://www.google.com/search?q=highway+vehicle+fi...mp;bih=549

I agree that prevention/reduction is important and it seems that removing this flammable foam is a reasonable tactic.

A few weeks ago I was stopped at a stop light on my 42 year old motorcycle and white smoke started billowing out from behind the fairing. Fortunately, there's not a lot that's quickly flammable so I was able to yank on the harness and eliminate the short to calm it down. The harness is melted back to the coils at the back of the underside of the gas tank. Had the foam been there... :shock:

Fire bad.

Sun Aug 18, 2019 5:46 pm

jimf909 wrote: While Vanagons certainly burn, there are plenty of Honda's and Toyota's on an image search in Google.

It’s feasible that fires are more prevalent in vehicles that run long enough to get worked on under the shade of a tree.
There was a point where Vanagons were thought of as another modern disposable car, thus received substandard care during that era.
Or cars that have “internet forums” that keep them on the road “longer than normal”.
Or vehicles wrenched on as a learning exercise etc.

———-

Westfalia has a mattress ontop of the engine cover, hard to believe messing around below 5 inches of foam will be audible. And its easy enough to switch back with another Vanagon to compare sound.

Mon Aug 19, 2019 5:43 am

real world results
I've had 2 vans come through my garage who had engine compartment fires.
and wile the fiberglass lid did eventually succumb to the fire(s) it was certainly not a spontaneous combustion. they in fact delayed the fire from entering the passenger compartment in about the time that you would hope/expect.

a proper method to FIGHT an expected fire would be more prudent..
maybe remove the spring from the license plate door inlieu for a HD magnet. so when you go to spray the extinguisher in there it's not fighting you.

also a blazecut or other on board automatic retardant

Mon Aug 19, 2019 1:27 pm

danfromsyr wrote:

maybe remove the spring from the license plate door inlieu for a HD magnet. so when you go to spray the extinguisher in there it's not fighting you.

That's a good idea right there, I think I'll be doing that in the next couple days. Thank you.

Mon Aug 19, 2019 3:14 pm

danfromsyr wrote: ...maybe remove the spring from the license plate door inlieu for a HD magnet...

I like the thought of a mini gas strut placed appropriately to both hold the door in the closed position and hold it in the open position.

Mon Aug 19, 2019 4:45 pm

Yes, an active fire suppression system is my next project.

My 5 cylinder makes the license plate hatch a bit less access then wbx , but still a good place to shoot into.

Not implying this project was the end-all. Just an experiment in materials that surely could be improved on.
I still think it's better than the OE foam!

Since all my screw heads are in the troughs of the corrugations, I think I'll probably cover them with another layer of something since it won't interfere with anything.

Mon Aug 19, 2019 4:53 pm

What do you think the market would bear for an exchange service for engine covers. Cracks in the fiberglass repaired, top refinished in epoxy gloss white. Bottom, engine side, stripped, cleaned and reformed with fire resistant foam in the original eggshell pattern.