Uncle Ernie: This is a Miller 35 not a 135. This welder easily could be thirty years old. It is a 160 amp machine. It was the first All-in-one wire welder Miller made. It is more of a commercial unit.
I already have several Miller welders: 251 and a 252. I have had issue with the circuit boards in both of them. Cost about $500 each time to get them repaired.