Welding machine help needed Hobart

Check where the torch goes into the machine. Pull it loose and clean up that lug and reinstall the torch. Letter F in the diagram. Most welders I've messed with feed power through that collar and can get some dust/crap build up. If the diffusor inside the nozzle is jacked up/ grounded out from slag it will also act like you describe. A couple quick checks before you run to the shop if you haven't already.

I'll also say this the duty cycle on the Hobart's isn't much and if you're constantly running past it they can be short lived and running them on insufficient amperage is pretty hard on them as well. It's not so much as how long it's been run as how it's been run.