Most of the time problems with your starter is your starter solenoid malfunctioning. Replace it with a new one and save money. These are starter solenoids for AC Delco starters on SA-200 Blackface welders. There are two (2) versions primarily in length - ~4" and ~3.5 inches measured from the bottom of the solenoid to the top of the housing (not the top of the bolts on top).
Please call with any questions 602-850-7399.