Lolly.
Its very disapointing when you have your heart set on something and it turns out to be a junker, Don't know what has happened to Marlins quality control. The older marlins are great in every respect. I have some of the older Marlins and they are like a good work horse. I do have two of the guide guns both are in 45-70 and the are fine, also have a couple 30-30s the older models. I would give Marlin a call and tell them what you have and they might make it right. Hope you get it to working like it should. Good luck.........Joe.............