N scale Streetcar

[Troopamg]

I have 5 PCC body style streetcars.  The main problem I encounter is that if I take them apart for cleaning and then reassemble them they do not run.  What am I doing wrong?  Since there are only a few parts it becomes a real puzzle.  Can the engine be tested and how do you do it?  Is Bachmann staying from the PCC and now sticking with the Brill?  I think the motor should be on the parts list.