Removing insulation and its glue from carpet backing

I recently removed the carpet from my Trans Sport van. There were some holes in the wheelwells where water and dirt were getting in. I welded the holes shut and wirebrushed and repainted the floorpan and wheelwells really nice. The insulation under the carpet was dripping wet, weighed about 75 lbs, and several ant colonys were living in the insulation. I want to do away with the insulation like I did on another car. It is not even noisier like I expected but would have been fine with, and it no longer retains moisture forever.



However the van insulation is glued to the backing of the carpet in about 5% of the total carpet area. Most of it just fell right off. But what remains is really stuck. I want it gone. What I want to do is remove the remaining insulation and its glue without damaging the black rubberish carpet backing. Does anyone know of a good way to do this? I started with a wirebrush, but I see that will wear through the backing if I were to continue. A paint scraper does not work. Anything I can spray on it to loosen it?

It isn’t hopeless yet. You can order new carpet from some ads in car magazines that is inexpensive and looks like the original. You can also kill the bugs and use floor buffing pads for insulation where you need it.

Solvents will likely attack the carpet backing too and potentially soak into the carpet so I’d avoid that route. My first choice would be judicious use of a heat gun to soften the adhesive enough to pull it free. If that didn’t work, I might try heating a razor blade (mounted in its scraper holder) and then pushing it along at close to the same angle as the carpet to slice it away (keep the angle low to avoid digging into the carpet backing).