H2o pump boiling

The cast iron was pretty clean on the outside, because heavily rusted metal leaves a brown foam. On the left you can see the bubbles in motion before they reach the surface. The star washer made a good bite from the cover plate to the pump itself because really rusty nuts and bolts won't conduct enough current to clean anything. The object is to keep your alligator clip out of the solution otherwise it will clean it so well that it will rust up over time.