Argh!!! Rust

[garboui]

well i just out washing my car. when i was drying off the car i had noticed some rust on the back wheel well inner lip just above the skirts. there is rust startin along the edge along with some small amounts of bibling on the flat as well. i pulled back the skirt and theres no rust behind that which makes sense because there would be no stones thrown from the tires to hit there.

what can i do to prevent this from spreading further? i am also planning on packing grease into the small gap where the inner and outer fender are spot welded together.

[PlatMS6]

I had the same thing happening to the 3 from about 60k... when it got to a 100k there was definatelly a lot of rusty pits (surface rust) on both rear sides (front was fine), hell you could even notice it 20 feet away walking to the car from that angle. Now Mazda is not responsible for this as the rust starts from rock chips, but the bastids should have had plastic liners in front of the rear tires!!!!!!!!!!!!!!!!!!!!!!!!!

What I was planning to do was to clean the area completely so that all of the rust forming was gone, and then tape off the whole area and spray the whole inner liner lip with first an anti-rust paint followed by a close matching body paint followed by 20 coats of clear coat in a can :p Another possibility was truck bed liner in a can, that would make it look like it had that plastic liner and it would definatelly protect from any further chips (this would have to be tested first), but you would definatelly need to treat the rust first before you apply anything.
Even if the paint was off it wouldn't be noticable, hell you could even use black anti-rust paint on that lip and only a fellow Mazda3 owner would be able to tell since most other cars have a plastic liner that extend from the wheel well covering that area.

If I were to buy a new 3 right now I would have 3M clear guard stuff applied to the inner fender lip the day I would pick the damn thing up.

I would definatelly do this sooner than later, because I see tons of ~2000 Proteges with rear fenders rusted to sh*t!

[garboui]

i think im going to brush in the seam between the two pieces of metal some of that rust converter solution. then sand, prime, paint the visable metal. after the paints dry i got some clear cravel guard taht i bought last summer to prevent this problem from happening and pack grease into the seam between the two sheetys of metal.