Electronics Help with Cheap tig unit.

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Saw a Panasonic 300WX on craigslist for 50$. Bought it with the intention of pulling parts out of it. Guy who sold it said it could not get hot enough and foot pedal did not work anymore, he thought maybe a rectifier was out.  Took covers off to start stripping it. Once inside, saw that it was an inverter design. It has a 3-phase rectifier, so I rewired it for 1 phase 220v. Was surprised when it fired up and the fan started to turn.Got my torch and ground clamps wired in, and hooked the gas up. Made a few test welds and need some help figuring out possible problems. I already know that the pot in the foot pedal is gone, thats why it wont adjust. The switch to turn the torch on and off works ok.It seems as though there is no, or little power coming out of the Electrode positive side of the machine. When making an aluminum weld, when the balance was changed more to EP, it just melted down the metal like what happens when you try aluminum on DC.  When changed balance to more EN, was able to lay down some ugly beads, what arc wanders all over the place and makes really wide beads.Also tried to run a 6011 stick on the machine. Got nothing but a stuck electrode and splatter. Electrode negative is getting next to nothing.Machine works great for DC tig, exception of the foot pedal not working. Postflow timer also seems to be jacked. In AC, after breaking the arc, it keeps flowing, only way to stop it was to tap the tungsten against the metal.  In DC, the postflow will never stop at all, even tapping the metal. Had to cut the machine off in DC.Balance - EP on left, EN on right. Metal just melts down into mess.http://imgur.com/a/SrvwU#4Not horrible looking AL bead. Added pulse and lowered current.http://imgur.com/a/SrvwU#0For 50$ I got a decent junker. Can rebuild the foot pedal and would make a nice DC tig machine. Any ideas with why the Electrode positive wont work, and the post flow would be appreciated.Album of all the pics I got are here.http://imgur.com/a/SrvwU