Hi i am having a problem with my welder it intermittently started cutting out , Not had it long so pulled of side panels and found very lose conection on 2 terminals to semipack, I replaced crimp connectors and repaired a couple of other badly done wiring repairs, after reading several posts on this forum pulled all 3 circuit boards and resoldered any bad connections, Still no joy every thing else works as normal wire speed control - gas valve - spot and stitch timer but no welding current, just small spark when you first pull trigger, I lastly replace semipack with skkt57b 12e but still no welding current, any help would be most welcome with wiring diagram and component specs