Hi folks,

I ran into a little problem with a project and need some help.

I took on a job to install a t-6 aluminum bung in the face of a Chevy BB intake manifold in the water passage just to the passenger side of the water pump bypass hose fitting.

I used a Syncrowave 180SD on AC, maxed out, 3/32 pure tung nicely balled, 3/32 4043 rod wave was set biased to penetration. I prepped it well removing all the casting flash on the aluminum intake and filed the surface of the bung fitting. Cleaned it with acetone and preheated it with propane to about ~300 degrees F. I had a hard time getting it hotter as the manifold was sucking heat fast.

I welded it and it looked ok...not great. Kind of dull grey..not shiney.

Bottom line...it weeps. I have to fix it again..and I am wondering if my machine has enough power to work with this mass of aluminum. 180 amps is barely enough for 3/16 and the wall of the manifold is a good 1/4 inch ....not to mention the rest of the manifold is a BIG heat sink.

should I have back gassed it when I did it to help with porosity... or is is porus from lack of heat and a cold weld?

What do ya'll say?