How can I fix my Yarman Self-propelled lawn mower?

I had the pull cord break on my yardman, even went to Walmart to pick up a replacement cord. For some reason or another, the Recoil Starter Assembly, the spring inside, stopped working. I ordered a new Recoil Spring and Pulley Assembly, got everything in place, but now, when I pull the cord, it doesn't retract back into the assembly housing, it just stays out. What am I doing wrong, and how do I fix this? Thank you!