W123 Sound Insulation - PeachParts Mercedes-Benz Forum

JEBalles · #1 05-04-2010, 02:44 PM

I've taken most of the insulation out of the 240 to make sure there was no rust festering underneath it, but after going on the highway for extended periods of time, I realized that what I tore out will need to be replace before my road trip. I know the difference between having the carpets in or out makes a HUGE difference. I still have the stuff under the rear seat. I did read in another thread that coating the fire wall with insulation and aluminum foil is good. Is that a good idea?

Does anyone have any good sources for good, inexpensive insulation? Sound deadening techniques?

I'd also like to not glue it down because I haven't fixed all the rust yet and I'd like to be able to take it up pretty easily.

JB3 · #2 05-04-2010, 03:02 PM

I used some of that bubble foam aluminum house insulation from home depot, and some aluminum tape. The stuff is cheap, and comes in a large roll, so you can double it as well.

JEBalles · #3 05-04-2010, 03:10 PM

Here are two that look too good to be true:

http://blujay.com/?page=ad&adid=2435115&cat=2020400

http://www.blujay.com/item/AUTO-BOAT-CAR-TRUCK-SOUND-HEAT-COLD-MOTOR-INSULATION-17060000-2433892

Is this the stuff you're talking about?

http://blujay.com/?page=ad&adid=2433212&cat=4010000

JB3 · #4 05-04-2010, 03:14 PM

wow, those choices are all pretty cheap. Does it give you any idea on how much you get in a roll?

Yeah, the third one is what Ive got for mine. It seems to work reasonably well. I got some spray glue to attach it permanently later on

Brandon_SLC · #5 05-04-2010, 11:25 PM

Here is an excellent product I found on Ebay. Very dense. I haven't installed it in my 240D yet, so I can't report on how well it works. Designed for yachts, but the seller uses it in classic British car restorations.

http://cgi.ebay.com/ebaymotors/Amazing-Sound-Stop-Foam-Sound-and-Heat-Insulation-Foam_W0QQcmdZViewItemQQ_trkparmsZalgoQ3dLVIQ26ituQ3dUCIQ26otnQ3d3Q26poQ3dLVIQ26psQ3d63Q26clkidQ3d876 1931302410949011QQ_trksidZp3911Q2em7QQcategoryZ34208QQihZ021QQitemZ310160210121

fdanielson · #6 05-05-2010, 12:14 AM

This guy has written up a number of things he did to reduce sound and the materials used to do it. I still have whatever the factory put in so don't have any personal experience.

http://www.dieselbenz.info/wiki/index.php?title=Making_your_Mercedes_Diesel_Quieter

chomptown · #7 05-05-2010, 01:18 PM

The replacement sound insulation is $52.89 which seems a bit pricey for something so simple. Napa Link

What do you all think of this stuff from Amazon? Its much cheaper/better, but he doesn't give the actual dimensions of the pieces he sells.

Or this stuff, also from Amazon. The dimensions are only 27 x 6, but it looks nice and thick.

big piece of Heat shielding

Brandon_SLC · #8 05-05-2010, 02:23 PM

Quote:

Originally Posted by chomptown

...$52.89 which seems a bit pricey for something so simple. Napa Link

... Amazon? Its much cheaper/better, but he doesn't give the actual dimensions of the pieces he sells.

The hood insulation from NAPA varies by location. My nearest NAPA is about $9 cheaper for the same item.

I followed your link to Amazon and found the size a little lower on the page. It's 24 x 48.

JEBalles · #9 05-05-2010, 04:09 PM

Fdanielson-great link, I might follow a lot of what that guy did. My hood pad is in reasonably good condition. It's dirty, but not torn or cracked. Expensive to replace, but I like what that guy did with his.

JEBalles · #10 05-05-2010, 08:41 PM

I think if I've going to go with the expensive stuff, I should go with dynamat. Is it worth the price?

Right now, I'm thinking I might just buy some of that cheap stuff and I can report back how it is. It can't hurt, and if I'm taking it right back up, I might not want to go with the expensive stuff.

Jeremy5848 · #11 06-29-2011, 10:36 PM

I ordered two days ago and received today 3 sheets of EVA (Ethylene Vinyl Acetate), a dense (heavy) rubbery material described as a "sound and vibration damping sheet." The supplier was McMaster-Carr; the total for 3 sheets with tax and shipping was $68. Each sheet is 32"x54" and is 70-80 mils thick. There is a self-stick coating on one side with a peel-off brown paper liner. This material and others like it are also available in the automotive and home sound system market but at two to three times the price.

I plan to use the material on the belly panels of both of my cars. The '96 has lost its factory pad and the '87 never had any. The purpose of the material is not so much to absorb sound as to damp out vibration, to keep plastic or metal panels of any kind from transmitting sounds by acting like a drumhead.

The EVA material weighs 0.75 pound per square foot (each 32x54 sheet is exactly 12 square feet and weighs 9 pounds). Enough to cover the rear-most panel of my '96 E300D will more than double the weight of the panel -- the bare panel weighs about 5 pounds and the EVA to cover it weighs 7 pounds.

EVA is reported in one web site to have "poor" resistance to solvents so it will remain to be seen what will happen when oil and diesel (especially biodiesel) gets spilled on it, as it inevitably will. I suppose I should do an experiment. If it doesn't work out on the belly panels it should do fine covering the interior panels of the car, especially since it's so thin and won't interfere with the existing coverings.

Jeremy

1980sd · #12 06-29-2011, 11:24 PM

I used this stuff I got at Lowes for about $20...

Jeremy5848 · #13 06-29-2011, 11:40 PM

How thick is it? Notice any difference after installation?

1980sd · #14 06-29-2011, 11:50 PM

It's pretty thick with a thick aluminum backing. I've used Dynamat before and this stuff is a little thinner but I think the aluminum is thicker. I removed the factory sponge rubber stuff and this works just as good.