Thank you. They are E-Z Mate I with the silly little plastic piece, so I think I will just replace them with E-Z Mate II or Kadee's. The Engine has the little spring on it though. Why they would not put the spring on them all is past me?! Anyways, thank you for your help.

Hello all you model train folk,
My son got a new Bachman Rail Chief E-Z track system for Christmas. We have set it up, turned it on, and played with it. It is a lot of fun. However, we are unable to make the the E-Z Mate Knuckle Couplers couple together. The instructions simply say to push the two cars together and the couplers should innitiate. They are not and the cars won't stay together. What do we do? I have taken a coupler apart to see just how it works and I got nothing out of this. I am not sure if they are magnetic or what? I imagine that it is simple as this set is meant to be simple. Can somebody please give a newbie some simple advice?

Thank you to anybody who takes the time to respond.