Tried to be nice and snowblow the drive and walk while partner was working. I got close to the front steps and accidently sucked the dog chain up inside the blade and it spun until it got stuck. I've tried feeding the chain through to unwind it but it seems parts of the chain are tuck on the screws inside. Is there a way to put the blades in reverse to unjam the chain from the blades? HELP PLEASE!