I am a fairly recent inductee to the 928 world and have been a lurker
few months. In September I bought my first Porsche. Of course it had to be
a 928. It's a 1982 US, 5-speed, Chiffon White, with 63k original miles. I
am the 3rd owner and I am in love! I don't have my website up yet but as
soon as I do I'll post pictures.
The car is in excellent condition with a few minor flaws. One of the things I want to take care of is the hood foam. It is quite dried out and is crumbling apart. I have the new pad on the way and was hoping to get some tips for removing the old pad and installing the new one. All help is greatly appreciated.
Andrew, since no one else posted to help you out, then I will.
Having never done this job, I do not think it should be that difficult. I have seen many a 928 with the deteriorating foam hood insulation from heat exhaustion.
My best guess is to do this job when the car is cool. Pop the hood and lay an old sheet or something over the engine compartment to catch any and all old foam.
Get yourself a wooden spatchula and start at the front most part of the hood working towards the back. I am guessing that this foam was originally applied with a contact cement. Scrape as much as you can off of the underside of the hood. Be careful of any wiring tucked into the side lips for lighting or what ever is there.
I wouldn't think it would be necessary to remove the old glue just as long as you got the surface area pretty flat. I would be hesitant to use a metal scraper for this, but it may be possible. I think you can get some pretty heavy duty sand paper to knock the high areas down.
Once you are happy with the removal, get a vacuum cleaner and suck any loose foam bits out of the lipped areas. Remove that sheet and throw the old material into a plastic bag. Lay the sheet back over the engine area so you do not drip anything on the engine during installation.
As for application of the new insulation, I would ask the party that you are purchasing from, what kind of high heat adhesive they recommend and instructions on application. It doesn't sound like brain surgery, but you just never know. Last thing you want is to be driving down the freeway and the hood insulation decides to take a dive into your fan and belts or maybe even shift and melt on something.
I replaced the hood foam on my '87 S-4. It is not that hard; just remove as much of the old stuff as possible, as follows:
1. Cover your engine with a cloth or something; the old foam will crumble
and is messy to clean up.
2. Use a shop vac to vacuum off as much of the old foam as possible. It comes off surprisingly easily with a shop vacuum.
3. Use a plastic putty knife to scrape off any residue. Don't worry about any excess glue.
4. Should you decide to use OEM hood foam from 928 Specialists or one of the other vendors, be careful when installing it. The replacement foam is a "peel and stick" application...you need to align the foam carefully and peel of the backing slowly...if you peel off the entire backing at once you run the risk of premature contact with the hood and won't be able to remove it
without damaging it.
I finally got around to replacing my tattered old hood foam on my 82 928.
If any of you have been contemplating doing this, it's really easy and makes for a much nicer engine compartment.
I forget who suggested it, but whoever said to use a shop vac to suck off the old hood foam was right on! I have a feeling it's not too different from doing liposuction. It comes right off and there's virtually no mess to clean up (although I still had a drop cloth in place.
The hardest part I found was getting the new foam in place. I think I found
the best method accidentally. First I sprayed some 3M super 77 on the
backing of the foam (oh yeah. some hood foam comes with it's own sticky
film. I got mine from 928 Intl which does not have a sticky backing). I
thought it was enough, but it wasn't. It was just enough to kind of hold it
in place. After I got it positioned (actually I thought is was installed
until I went for a drive and found out later that the foam was coming off).
I then peel the top half off again and really doused it with the 3M spray including the hood itself. Then I did the bottom half. SO far it's holding up great and it looks loads better! Thanks to all for the kind suggestions.
Now go out and do yours, you'll be glad you did.