I have a 1958 10HP Johnson Seahorse. Just recently the pull start chord stopped working. Whenever I pull on the chord, the chord comes out and retracts as it should, but something is not engaging and there is no resistence in the chord. It looks like the plastic "arm" that turns out and makes contact with the flywheel never moves. If I remember correctly, this should move and engage to move the flywheel. Is there a way to fix this? Any help is appeciated. Thanks