Dialarc 250 AC/DC fried?

[robo93]

Greetings,

I purchased on old (mid-80s) Dialarc 250 AC/DC (no HF) stick welder about a year ago on bookface. The machine worked just fine but I hate the plug type receptacles and wanted to convert it to Dinse-type in order to be able to use the a common set of leads between machines. When I opened the box up, I noticed that the rheostat was in less than great shape and could see the play between the dial and the arm on the rheostat so I decided to replace that as well. I could feel it giving a little bit previously when changing amperage but this was the first time that I'd seen it. I found a replacement 15-Ohm 150-watt rheostat to replace it and bought a new dial as well for good measure. I changed out the plugs for new Dinse-type terminals and changed out the rheostat and dial and fired it up. The machine fan started just fine, like it always has, but when I tried to start an arc to test it out, I heard a very quiet <click> and then the fan shut down. There was also the slightest smell of ozone, but no flashes, no smoke, nothing else. I checked the terminal cables and they weren't touching. I know that I hooked the rheostat up correctly because I went directly from removing one wire from the old rheostat to replacing it on the new one. Nothing was cross-wired, nothing else was done to the machine.

My question is, based on this very admittedly limited information from a neophyte welder repairman, what are the chances that I've fried a board or something similarly expensive? I didn't pay much for the welder and am really not interested in dropping hundreds of dollars in repair costs if it can even be repaired, but I would like to have it operational again. Any idea how expensive it is to have somebody even look at an old dinosaur machine like this one? I love the thing and am hoping that it can be fixed. Something about the ungodly heavy transformer machines just appeals to me.

Anyway, thanks for your time!