My Doors Are Rusting Again ! Anyone got a good fix ?
The last time around I wire brushed the doors down to bare metal. Used a zinc based self etching primer, went over that with paint. I then put new rubber strips on the bottom with silicone to seal them off. I now have the rust back again. Looking for suggestions on how to repair this problem once and for all.
Hey Derek...not sure exactly what products you used (m)
...but last Fall, I went through this myself after reading this was a common problem with the E34. After pulling off the strips from all 4 doors, turned out only my driver's door had any rust, so I lightly sanded it and applied a few light coats of POR-15, followed by a thin top coat of Chassiscoat black (same company -- no affiliation). I haven't seen any rust, however, I also never reinstalled the rubber strips either. Seems they're good at trapping water in there.
Anyway, I've used POR-15 on old rusty floorboards of my old jeep, and a handful of other auto and non-auto applications, and I've yet to see any rust return. Just my $.02....YMMV.
Hope that helps,
Tim G.
'91 535iM
you have to "neutralize" the rust first.
there are many product for this but i cant think of one.....check out your local hardware store, "anti rust" primers will include a reference to some prior treatment.Remember.....rust never sleeps
Rust Mort turns rust into a black looking rust thats supposed to be paintable but you
cant sand it prior or after treatment or it wont transform it. If it has rust pits to do it correctly you have to use an acid wash to get the rust out but make sure to wash all the acid out (baking soda) or you will paint the rust and caustic acid in there which is not good (ask my old 57 Dodge that I gave away to a good home)