Hi everyone I'm new here but not new to the hobby. I pick up a class j n scale from modeltrainstuff mbklein. It a great loco. Excellent pulling power my pulls 14 passenger cars up my 3.64% grade. But there's one problem. The side rod linkage keep s falling apart the first time it happened one my first class j then I thought it was a bad model, so I brought a new one. Two months later same thing has happened again. So I sent both for repair 90$ out my bank account.  Week later got my two babies back. One was missing parts runs like crap. The other runs fine until the linkage to the Pistons broke again!!! Has anyone else had this problem.