[69ChevelleAddict]

What the heck is in my trunk!?
Wish i had a picture to show you guys but i dont and cant afford a camera with all the projects i got going on.
ANYWAY, it is rough black "stuff" everywhere in the trunk, it looks like it was sprayed on, i have some flaking off in some areas.
I know its not the stuff that came on the repop trunk because that stuff is still on there as well, just under the other black gunk.
Upon further inspection it looks to be hiding a whole lot of this hard rubber type stuff, its orange/yellow and somewhat flexible.

[pigman]

black textured stuff all over the metal is 99% tar.. real pain in the ***.. trust me.. i have it too, so do many others

it is a type of rustproofing

[69ChevelleAddict]

Well it didnt work so well, the rust is starting to regroup and attack!
Well not really its just surface shtuff for now.
I took out the drain plugs and hit them with a wire wheel, took it down to bare metal with very little effort.
I think tommorow pending apporval from my car guy boss i am going to crawl arround in there with the wire wheel and grind the piss outta it :

But any idea what the orange/yellowish rubbery stuff is?
That stuff is everywhere there is a seam and it really looks problematic, like it is hiding some bad welds or something.

[Early B's]

The black gunk is an asphalt/petroleum based undercoating that also works well as a sound deadener. Best way to get it off is by warming it with a heat gun (not a blow drier - doesn't get hot enough) and then scraping off with a putty knife. This will get the big stuff off. To get the remaining leftovers you can use solvent or even aircraft paint stripper - then wipe with rags.... The yellow rubber stuff is probably seam sealer. Just wire wheel it off.....

[pigman]

I have read in other threads, the best stuff for getting tar undercoating off is oven cleaner!

[69ChevelleAddict]

The balck stuff is weird though, it is dry, non sticky, starting to flake and comes off very easily with just a wire wheel.
I think i have a little of that petroleum stuff in there as well but not nearly as much.

[OneMoreTime]

Probably what has happened is the old undercoat has dried out over the years and is now brittle and dry so it comes off fairly easy..I suspect in the thicker areas it may still be gooey...At least that is what I have found in these old cars..

OMT

[rrmccabe]

By the way, the yellow-orange stuff used to be white

Its just seam sealer as someone mentioned. If its loose and pulling away its probably hiding rust as you said. Good idea to remove it, wire wheel (or my favorite deals 3M clean and strip wheels) and reseal it.

Have you tried any lacquer thinner or even gas on the black stuff? If you can soften it you can scrape most if it off with a putty knife. Saves a lot of dust and mess.

Rich

[alden]

Originally Posted by Early B's

The black gunk is an asphalt/petroleum based undercoating that also works well as a sound deadener. Best way to get it off is by warming it with a heat gun (not a blow drier - doesn't get hot enough) and then scraping off with a putty knife. This will get the big stuff off. To get the remaining leftovers you can use solvent or even aircraft paint stripper - then wipe with rags.... The yellow rubber stuff is probably seam sealer. Just wire wheel it off.....

heat works, but it's messy, honestly the easiest way to get this stuff off is to freeze it and just chip it off, take some dry ice, spread it around the area, and then take a chisel to it, it'll just pop right off in large chunks, leaving little to no residue.