RayChez,
When I started working in a auto shop, at age 17, I also heard the welding on, or around an engine would completely ruin an engine, by welding the rod, main, cam bearing to the crack and cam. Well.....Guess what, there has not been any engine ruined by welding on the block, head, intake, or exhaust. I would imagine that if you placed the ground on the crank snout and tried to weld the block, you might have a problem, but I doubt it, as everything is oil coated. Electricity is like water, it is lazy. It will take the path of least resistance.
