The nice thing about poured bearings is the fact they're thick enough to be scrape-fitted. A thin layer of Prussian blue identifies the tight spots, which can then be scraped with a razor-sharp tool made by hollow grinding a 3-cornered file, gently removing the high spots in the bearing material. Once there's just a smooth blue smear with no shiny streaks, the bearing is an exact fit to the crankshaft journal, and shims can be added to establish the right oil clearance. A smooth, round crankshaft and a little time and effort fitting bearings can result in a better fit than most insert bearings can achieve.
Jerry
