The side I experimented and cut the rusty sheet metal out and filled with body filler seems to be holding up well. No worries about moisture in the foam, as the expanding foam used is sandable filler used for filling holes in boats, homes, etc. And then around that I used a layer of Bondo fiberglass filler, then Bondo body filler. The other side that I just sanded down and painted over the existing metal does have some rust coming back, so I'll have to cut that out and fill it too.Jothro, how is your fix holding up? how long ago did you do it? does the foam absorb moisture?
Oh boy, good question... I don't remember if it was a specific type of Great Stuff, or if it was another brand. I'll have to take a look to see if I've got any left overthanks guys. I did several body projects 35 years ago and have all the tools. Did you use great stuff original foam
Mine rusted in the same area on both sides.hmm I don't know if this is rare but my malibu has never gotten rust in that area also in my opinion I would assume that if you do fix the rust properly that is then it shouldn't come back unless the area/paint gets damaged somehow I only assume this because my car has never gotten rust in that area to begin with
Mine rusted there on both sides . Pull the plastic rockers off. You'll have to buy new clips as the old ones will break. Grind off and cut away bad metal. I went to home Depot and bought a small piece of sheet metal and cut n' bent pieces on a garage vise to fit , JB welded and riveted the patch panels on, layered on small strand fiberglass filler , sanded and finished with bondo, primed and painted with White Rustoleum enamel, finished with clear coat. Should last me awhile. Don't let it go longer . Chances are it's bigger than what you see there. My cost was 200.00 dollars including tools needed and supplies from Harbor freight as opposed to 2,000.00 dollar quote from a body shop. Chaulk it up as a fun learning experience. Mine came out fine for a first time job. Just take your time
I saw that material in there as well. I think it's to deaden the road noise coming from the rear tires . That's my guess.I see one reason they rust more on that spot. When opened up it is full of a blueish green fibery sponge like material. I took some of it and it absorbs and holds water.