Newbie with no arc on millermatic

admin

Hey everyone, to begin i am just a hobbyist and rarely weld. I dont know much terminology when it comes to this stuff, so bare with me. I have a millermatic 250x, that was given to me because it didnt work. I found out the circuit card was shot and replaced it with a new superseded card. After that the welder worked great. Now a few months later i try and weld a bracket on my trailer, and am not getting an Arc. The wire feeds fine, the metal is clean of rust and paint, the ground has a solid connection (tested with meter), but now i have reached the end of my limited knowledge. Does anyone have any ideas on what and where to check.  And if you could break it down barney style please.  I have a attached a few pictures of the inside of the welder.  Attached Images