Some Engine Compartment Questions
 

Hello Ladies and Gents,

I am currently cleaning up my 83 SC engine compartment (horrible task) and came across a few things I am wondering about:

1. Found this little contact switch that touches the lower right hand corner of the decklid when raised or lowered. Is this a factory switch of some kind? My guess is that it is not, only because I removed an aftermarket Python alarm system a few years ago and I am thinking this is a leftover from that system. I was never able to find a wiring diagram for the alarm so I dont know for sure. Another hint is that the switch was connected to a green wire that runs separately from the factory harness but is zip tied to the factory harness.

http://forums.pelicanparts.com/uploa...1515042038.jpg

http://forums.pelicanparts.com/uploa...1515042038.jpg

2. As I was poking around cleaning the engine compartment surfaces I found that behind the crossmember that contains the shock towers, in each upper corner there is an opening where the AC hoses and some wiring pass through down underneath the floor. In each opening I found a block of foam shoved in there, I assume to seal the cool engine compartment air from the hot air below it. I removed the remainder of the foam because it was crumbling and was literally just shoved in there so it didnt look like it should belong there. Is that foam factory? If not what is supposed to seal that opening on both corners?

http://forums.pelicanparts.com/uploa...1515042549.jpg

This is the view from inside the engine compartment, right hand side:

http://forums.pelicanparts.com/uploa...1515042853.jpg

Below engine compartment, right hand side. You can see the opening via the light shining from inside the engine area.

http://forums.pelicanparts.com/uploa...1515042853.jpg

3. Finally, can someone recommend an effective chemical to remove the dried sound pad glue on the firewall?. I am thinking of possibly leaving the pad off so I would like to know how to clean that surface off as best as possible without marring the paint underneath.

http://forums.pelicanparts.com/uploa...1515043444.jpg

Thanks in advance. :)

The switch is aftermarket, probably from that cancer of an aftermarket alarm. Mine had something similar.

The foam is sound deadening I believe. Not sure is the p/n is the same for my '87 as for your '83, but on my '87 that foam block is p/n 911 504 930 00.

A-ha! So leftover chunks of sound deadening foam stuck at the bottom corners. I remember I removed whatever remained of my sound pad and it came off in pieces.

Must do double-duty to seal the air gaps at the corners...

The foam blocks to seal the gaps (as referenced by wrxnofx above) are different from the sound pad that goes on the back wall of the engine compartment. Those blocks are inserted from under the car in the gap between the engine box and the main body. Given the condition of what you have, you should replace the two blocks, as well as the sound pad (you have aftermarket options for the sound pad as well; Pelican offers a number of them).

I'm in the middle of this myself... http://forums.pelicanparts.com/porsche-911-technical-forum/978748-engine-bay-cleanup-some-input-please.html

A heat gun and scraper worked for me to soften the glue and scrape the majority off. WARNING: keep your heat gun away from fuel lines! Other then that I used a wood stripper bit for my drill-- the sort with plastic fingers. Worked to gently remove glue without doing any damage. No chemicals I tried would touch the glue in the least bit.

As far as general grease and grime removal, several cans of brake cleaner will do wonders. A respirator with good carbon filters is a good idea, and be aware that brake cleaner will also remove paint. I'm repainting the bay so that wasn't a concern for me.

Good luck!

Thanks for the input. Ill yank out the contact switch, source those foam blocks, keep cleaning, and might try some adhesive remove before resorting to the heat gun and minding the fuel lines.

Also, Evan, thanks for linking your engine bay cleanup thread, I now know how to tackle the heater boxes as well!

why is there a cracked opening in your engine compartment that light can shine through???

That's really odd... I've never checked mine, but I would imagine that there shouldn't be openings like that.

You're welcome! SmileWavy

One thing to consider is that I'm repainting the engine bay, and on re-reading your post I realize that this doesn't seem to be your plan. I think that it is not possible to get the glue completely removed, and certainly not without removing paint unless the adhesive remover is magic stuff (I didn't have any.) So if you're going without a sound pad as I am, I doubt you'll get the glue away but still have a presentable firewall. If you succeed, do let us know what worked!

After scraping the glue off I coated the firewall with a undercoating type textured paint called bodyschutz. The bodyschutz is paintable, so I'll do two coats of color followed by two coats of clear to protect the paint. The factory paint in the engine bay acts as though it never had clearcoat, as a little application of brake cleaner and my paper towel is blue...

It took a lot of effort to get 36 years of grime off the upper surfaces in the bay. Brake cleaner, citrus cleaner, scraping with heat, abrasion, degreaser, powerwasher, etc. I was able to have the original color custom filled into rattle cans, so the paint job won't be to difficult.

Maybe my description was not the best. If you reach in the corners behind the shock towers there is an opening on each side. I didnt notice them until I pulled the AC lines out and took out a few chunks of foam in the process. Then I kept prodding back there and there was more foam, which I pulled out. Ill see if I can get better photos this weekend as I dig back into more cleaning.

No. 12 on the PET are the foam blocks being discussed.

http://forums.pelicanparts.com/uploa...1515203700.png

Would you look at that...P/N 91150493000.

Thanks Tony!

3M adhesive remover works. I found it at Autozone. Spray and brass wire brush small areas. It softens the glue, but dries quickly. You can only clean roughly 4" square areas at a time.
It works but is time consuming. I finally gave up and put a wire wheel on the side grinder for the bulk of it. Repainted when done.