The electric cord plastic jacket melted and burned through wire on one spot. Can the cord be replaced

I am currently attempting to do that myself. You need to separate the liner from the outside part. Using a pair of pliers, loosen the round nuts (found on the bottom) holding the unit together & separate. You'll find that the unit won't come completely apart because of the wiring. There is a heating band, held together by a spring, around the inner liner. Remove the spring to release the band. This should allow you to remove the inner liner & give you access to the wiring. At this point, you'll need to clip the appliance cord by the little wire nuts. The hardest part will be getting the cord out; there is a strain relief grommet that holds the cord in place and prevents it from being cut by the sheet metal where the cord goes through. I broke this strain relief on my crockpot and am currently looking for a replacement. Once I find a cord relief, I should be able to reconnect the wiring, the heating band and assemble the unit. Be careful not to cut yourself on the sheet metal!