I bought a Lincoln ranger 250 a few months ago. It was made in 2005 and has sat in a shop all its life. It had 57 hours when I bought it. The guy put a brand new battery in it right before I bought it. I started it up and ran a few beads and then took it home. Ever since I bought it, I would run it and after I run anywhere between 5-25 rods it will just decide to stop welding. No arc at all when I try to strike it. The generator will still idle up and provide power like it should and everything else work other than no arc. I have blown the whole thing out with compressed air, cleaned all the grounds, cleaned the slip rings and checked the brushes. Leads are in great shape with good connections. Nothing has fixed this and I cannot figure it out. Any help would be greatly appreciated!