Thanks. I did clean the nickel silver track and it seems to have fixed the problem. I'm curious how brand new track can get dirty in only 3 weeks.

I purchased the Freightmaster starter set a few weeks ago. One week in and the engine started hesitating and screeching at times, so I returned it. Got a new engine. One week in and this engine often just stops on the track at a few places and needs a push to keep going. This happens at slow speeds. I usually just have it creep along during the day. I've added a number of cars to the train and added track to get a figure eight. Should I just return this one as well? Are these starter set locos of poor quality? Seems like I'm doing something wrong. Thanks.