I had an hour today and i did get it to work. I pulled the diodes out and checked, they appeared to read good, all were very close in reading. I scoped the output dc and had minimal ac on the line. The fine current adjust was checked with a fluke and also appears to be good, a couple bad spots in it where we always have it set at, but not causing the problem. I then had someone weld with it and it welded, with both the range switch and fine current set to minimum. This was with a large electrode, so i could not get a nice thin weld as it used to do. I then took off each lead # 17, 27 and 37 one at a time and tried the welder out at the above mentioned settings. # 37 did the trick and the unit operates as it should. This is without one of the three coils of the reactor. Can i now assume that even tho the coils all read the same, the one associated with #37 has some varnish worn off and allowing part of the windings to short together? I did not have time to read individual coil windings and am not even sure it is possible. Will it badly damage the welder to operate it this way? We are lucky in the fact that we have 4 other welders that are newer and nicer than this one, i just did not want to trash this one......again, thanks to all of you!!!