Glad you got it sorted. I looked on youtube and I could see a fellow pressing off the bronze worm gear from the crank using a special tool, but he didn't show how he got the washer/cover off. From your photo, the cover appears to have a hole (two?). Are those holes threaded so the cover/ washer can be pulled off with a puller? Did you find the plastic gear inside was broken? There is an echo CS-680 near me (Utah, western US) for $400. If I needed one...