Welcome to TBN! But I do wish that newer members would give us at least a brief profile! Like where you are, State, Town, and the tractor and equipment numbers!! There lots of people here that can almost "walk-you-through" the repair, and have search capabilities, that you may not think of. Some of the JD Exploded drawings cannot be of help, without the specific 'Blower-Thrower' model number!! My experiance has been that I buy #50 roller chain, and a master link, and with three bolts to remove, and loosing an idler assembly, this should be an easy fix........~Scotty