its cast ally, not really weldable like that, my mate works for a place that has repaired ally heads, they have to be put on a heat block table, and then the head has to be heated up to a certain temp, then welded with proper rods, normally stick welded, then cooled down very gradually over the course of hours.
imo, your better off getting another head. im sure there are plenty on here.
stick a wanted add in the wanted section.
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