welding valve cover

[medieval]

I am a welder and thought that I would refresh my valve covers by building up material then sanding back the excess. Does anyone know the magnesium alloy of the valve covers? Anyone try it that could give me tips?
:help

[PUDGYPAINTGUY]

I use a product called alumalloy on my engine stuff and other stuff too. They make weld rods for every kind of stuff, and it does work very good too. Big money saver on older expensive casings. Here is the link, hope it helps you too.
http://www.alumalloy.com/