MacDon 974 feeder draper problem

I'm running a MacDon 974 on a Case 7010. I recently started having problems with the feeder (center) draper not starting up when I engage the head. It would only move slightly if I ran it forward or backward but eventually would start working in reverse and finally in forward. I don't think it's a tension problem. Just wondering if anyone else has had this problem.
Thanks in advance for any help.