Re: Paint cast iron drain pipe
When painting the main stack that ran through my bathroom (veritcally) I ran into the problem of what primer would stop the original asphaltum coating from bleeding through (it apparently was coated from the factory to keep rust away until it got assembled) I primed it with the primer that was going on the walls (BM oil based enamel undercoater) and I discovered the stain bleed-through. Then I switched to some shellac, which I thought would stop it, not entirely. Finally out of desperation, I grabbed the thin PVA primer I had used on one section of new drywall before tiling. That seemed to do it; after one more coat of shellac, I put on the semi-gloss acrylic paint, and no more bleed.
Remove not the ancient landmark, which your fathers have set.