Underhood Pad - PeachParts Mercedes-Benz Forum

stephenson · #1 08-25-2003, 03:48 PM

I need to replace mine (1991 350SDL) ... getting a bit brittle and beginning to detach somewhat.

I did this years ago on a BMW and, if I remember right, ordered a reflective metallic and foam (about 3/8" thick) blanket and trimmed it to fit. Anything like this available? Or, should I go with original ...

Has anyone on the net replaced one recently?

Thanks.

1991300SEL · #2 08-25-2003, 04:55 PM

http://www.peachparts.com/shopforum/search.php?action=showresults&searchid=540425&sortby=lastpost&sortorder=descending

davidmash · #3 08-25-2003, 06:03 PM

I bought a factory pad. Used some 3M adhesive and smacked it on. Been 2 years in TX heat and no problems.

kpr · #4 08-26-2003, 06:00 PM

bought a pad from e-bay - $40 - used liquid nails to adhere it - no problem and very easy to diy

Benzwood · #5 08-26-2003, 06:40 PM

The OEM pads have a special metallized portion, the whole pad isn't metallized. Don't know if it makes a difference.

Last I knew, you could still get MB OEM pads for diesels... I got one when I tried to order a pad for my 300E... apparently they don't make the gas version separately any more.

I didn't like that metallized thing so I swapped mine for an aftermarket gas pad which has worked fine.

I used 3M Super Trim adhesive to attach. Over a year so far, no sagging or problems.

A previous thread with photos

Phil at PartsShop can take care of you.

git0 · #6 08-26-2003, 08:57 PM

Try This procedure by Dan Penoff that I saved as a word document. It worked for me. I used the 3M spray adhesive and the MB adhesive. BE SURE TO COVER THE FENDERS AND ENGINE COMPARTMENT WITH A SHEET UNLESS YOU WANT TO SPEND HOURS GETTING THE OVERSPRAY OFF.

Replacing your Hood Pad
By Dan Penoff
1. Raise hood to full vertical position
2. Find junky sheet to cover whole front of car/engine compartment
3. Get hard plastic scraper (a windshield ice scraper does very well, and I have no current use for one where I live anyway!) and start scraping
4. When you get the adhesive see if the supplier has 3M Adhesive and Decal Remover. This is really nasty stuff but will not harm automotive finishes other than to strip the wax off. Very flammable as well, so don't do this around the water heater or enjoy a Macanudo while applying it. Soak a shop rag in the stuff and get it all over the remaining gook from the old pad. Since it's mostly naptha it does evaporate quickly, so work in small areas. Once the remains of the pad are softened up scrape away! Don't obsess about complete removal, as you won't get all of it off. Some people use metal scrapers such as putty knives which are pretty dull, but I prefer not to. My concerns are that scratches in the finish could possibly rust from moisture trapped in or under the pad. Certainly don't want my hood rusting from the inside out!
5. Once all this is done carefully apply the adhesive. I say carefully since it will attack painted finishes on you car, so spray close to the hood and avoid any overspray. I like to spray a 4"-6" section across the top (front) of the hood with a corresponding application to the pad in the same area. Let the adhesive set up the prescribed amount of time.
6. Get the pad lined up and stick it on in one corner. Line it up on the other corner and make sure it's in place, then press it down. Now the pad will be hanging curtain-like from the leading edge of the hood.
7. Apply the remaining adhesive to the hood and pad and press it into place after it sets up. I have a brayer (a hard rubber roller used for laminating) that I like to use to go over all parts of the pad, making sure it's stuck on well. Leave it in the vertical position for an hour or so, then you're done!

Benzwood · #7 08-26-2003, 09:15 PM

Good advice, except that I would skip the adhesive remover step. I just scraped off the big chunks and called it good... personally I don't like the idea of spraying adhesive remover around paint, no matter how well covered.

I also did not use a roller to press it down, just clamped it with my hands on either side of the hood.

The 3M Super Trim Adhesive (specifically Super Trim, not the regular) is good stuff. Application is well-controlled (think silly string). I followed the directions on the can for spraying on both surfaces, and one can is just about perfect for coverage.

One other note -- before applying adhesive, test fit and make some alignment marks (I used masking tape). And when you put it on for real, get a second person to help. It's a big flapping sticky pad and two hands are not enough.

AMG CE 36 · #8 08-27-2003, 02:53 AM

I am thinking of doing the opposite, removing the pad. Only because I think it is too effective in keeping the heat inside engine compartment. Without it I hope the steel in the hood is better in transporting the heat out. Maybe I should keep the aft part so the electric side is protected.

But, the noise? Has anyone experienced if there will be a lot more noise running without the pad? Any other disadvantage to consider?

Rgds/L.

Benzwood · #9 08-27-2003, 10:35 AM

Probably be more noise, but more importantly I think you'll cook your hood paint.

Also the gaskets around the electronics by the firewall rely on the hood pad being there to make a good seal.

The car is designed to have the seal... if you're having overheating problems, I'd find the source of them and fix them rather than taking that step.

driad_98 · #10 03-14-2004, 09:47 PM

Anyone know what happens when you use the 3M General Trim Adhesive instead of the Super Trim? (whoops)

TIA

PaulH · #11 03-14-2004, 10:00 PM

The General Trim stuff may be affected by the high heat. The Super Trim is not supposed to be affected by heat. SO, don't sit in traffic in the summer.