Problem with my dads old train set.

Hi guys, just another NOOB, coming here with my hat in my hand, asking for help. I'm having an overload issue with this lionel train that belonged to my dad. It will run for 10-15 minutes, then the train just stops. The overload light on transformer then comes on. The light on locomotive is on, but the train isn't moving. If I move the switch on top of the locomotive, it will start moving again in reverse. I can then stop it and get it to run forwards again for another 10-15 minutes before it does it again. The tubular track is new. The transformer is 2 years old. I am using a piece of smart track for the power connection to the transformer, and have adapter pieces at both ends of it to cross it back over from fastrack to tubular. I have included pics of what I have, and will be very grateful to you all for any ideas or suggestions. Thanks.