I had some welding done on my valve cover but there are some voids in it. What could I use to fill in the voids and handle the high temps?

 

If you are just going to fill it for paint, JB weld would work great. If you are going to have it powder coated, it needs more welding. There is also a "body filler" for powder coating, but I have never used it, so I can't really give any advice.

 

Jb weld... great suggestion!

 

tig weld it right this time..

 

Really, take it back or take it to someone else to get it done correctly. There should not be porosity after welding.