TIG weld a AL head?

There is a trick to getting all the oil cleaned out and cooked out of the aluminum poures, so it will weld good.

Degrease it well, then wash with boiling hot dawn dish soap, and rinse with distilled water.

Blow dry and let it sit in the hot sun for a couple hours, then go right to welding it while it is warm.

Won't Warp

Some folks even go as far as taking an old dishwasher and do a hot wash cycle with Cascade and and a hot rinse.

Some also use 20 Mule Team Borax to clean aluminum too.