This is an image of a blower housing from an Otto Canedy forge blower that I'm restoring. After removing the oil film and years of crud that has accumulated on the casting I notice what appears to be a casting flaw. I would like some help from someone who has experience casting iron.
I think the flaw is from iron that started to set before the pour was complete. I'm not sure if I'm correct. The line is on both sides of the casting. It doesn't look like a crack. What are your thoughts?
Click image to expand
I think a crack would have held oil residue that would seep out and leave a film along the flaw line. Also the crack isn't a mirror image on both side. My last thought was that some of the crack line is fine while other parts of the line are wide with what looks like the edge missing material. No light show through.
Your opinion? Thanks