11-10-2021, 02:55 PM
My understanding of the blistering is something called galvanic corrosion. Just google "galvanic corrosion under paint" and you can read all about why it happens. To fix paint gets stripped off, area gets prepped and painted over.
Brad Aden
2003 Newell #653 Quad Slide Cat C-12 engine
St. Louis, MO