I was wondering what would cause the dc loco to get hot?As long as your still DC just place the loco on the track and allow it to run slowly in one direction for about 10 minutes and then reverse the direction for about another 10 minutes and you should be fine. It still might sound a little noisy at first but not to worry it will be fine once it's been run some more.
If your running a DCC track and the loco is DC place it on the track and use the address of "0" and don't run it more than the 10 mins in each direction before you put a decoder in it. Also check for excessive heat inbetween the 10 minute intervals. DC loco aren't really meant to be run on a DCC track but won't hurt most in short intervals.
Hope I answered your question. If not or additional questions arise just post back to this thread and someone will assist
"Enjoy it's built rite in."