Seems like if it actually bubbled that the prep was lacking in some way. You
should get some protection, far better than bare metal from oil based
primers.

There are some metal etch epoxy primers that also come in a spray can which
I have found work quite well.

Bare metal is usually difficult to prime with no etching element.  Even if
you wipe it down before with an etch prep you will get better bite to the
primer.

----- Original Message -----
From: "Florian Speier" <groups.florian@GMAIL.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, October 14, 2009 2:32 PM
Subject: is primer/sealer weathertight?

> A few weeks ago I did my seams and surrounding three inches, at the
typical
> rust spot where the camper stuff is welded in on the drivers side. I ran
out
> of time after applying primer/sealer and thought thats ok to wait a while
at
> this stage.......
> now we had two days of solid rain, and I have micro bubbles under the
primer
> about an inch away from the seam, and worse, something slightly
rustcolored
> at a few seam spots.
> Obviously I have to redo a few things, but I was wondering whether my
> assumption that primer sealer is weathertight was wrong, or if I did the
> whole thing wrong......
>
> thanks
> florian