I recently acquired a 1989 HMMWV M1038 from an individual. The batteries that were in the vehicle were completely dead so I took them to O'Reilly Auto Parts to swap them out with a new set. The vehicle started up and ran fine with no apparent electrical issues for a few days but then it quit starting up so I opened up the battery compartment and realized one of the negative terminals that was connected to the battery cable had severely melted. I removed the new batteries and took them back to O'Reilly where they replaced them with another new set. Then the same thing happened, the vehicle ran well for a few days and then quit working and to no surprise the same battery terminal had melted again. Any ideas what could be causing this? I have included a few photos for reference. Any guidance would be greatly appreciated!






Thank you,
Stewart

 

it would help if you do not change the font color to one that can not be seen.
but you must have excessive current drain that can happen when there are loose or corroded connectors. that usually causes things to melt.
by the way all those connectors in the battery box look excessively corroded. maybe start by taking them apart and cleaning them then put them back together. do the same for any main battery connection and your main grounds. also check your starter for looseness and its related cables for corrosion.