Recoil starting problems with 5269D Lawnboy

Hello - ever since I picked up this model 5269D White top Lawnboy it's had, what I considered an extremely short rope pull. The other Lawnboys that I run have a longer rope, but since the 5269D always started Ok - I just left it alone. A few weeks ago I was showing it off to my BIL and when I pulled it over it just slipped and didn't engage. It recoiled fine, but I could only get to engage about every fourth time or so, or if I changed the angle of my pull. I removed the recoil assembly and checked the plastic gear and the spring clip on the shaft all held on by an E clip. Since I don't really know what I'm looking at, is it possible that the plastic gear on the spiral shaft is worn and is slipping or something more involved? I would also like to get the correct diameter and length of pull rope. The spring tension appears to be OK - so I don't believe the spring is broken.