250g trouble. can someone help?

[oliver66]

my welder has a mind of its own. sometimes it will weld.. sometimes nothin. nothin means no weld or receptacles. years ago i had to change the capacitor. so i changed it again. also years ago.. miller had put a 9volt bat inside with a push button on it to jump the capacitor. worked for a longtime with no probs. ive changed the capacitor and bat and im still having the problem. once it ever strikes you can weld allday long.. but if u shut it off.. it may take two hours to get it to strike an arc again. what in the world is goin on?