I'm not quite sure what your issue is. Are you saying that as you sew, it kind of gathers up, so you have to pull the thread to get your seam to lay flat? Or, are you just pulling the thread to the back side of the presser foot so you can start a seam? If that is the case, Do you know that when your presser foot is down, the tension is engaged. When the presser foot is up, there is no tension on the upper thread, so it should pull easily.
If you are getting a good stitch, I suspect it's the presser foot being down that is your issue.
If not, explain it in more detail, please.
bkay