My first thought was the heater coil. Since Appliance Parts Pros is my go-to for parts I ordered a heating coil, a high temp thermostat, and a fuse with examining first. When I opened it up I found one lead to the coil was burnt off and the other showed sign of heat at the terminal. I theorize that over the 35 years of use corrosion occurred at the crimp-on terminals going to the heating coil. As the corrosion increased the resistance at the terminals increased until it melted off one terminal and the other show sign of excessive heat. I replaced both terminal connectors with new well-crimped connectors and silver soldered for extra assurance. Should last another 35 years.