Remove the entire cowling (not a big job). Remove the starter pulley (may involve bending retaining tangs on cowling). Replace rope. Pre-tension spring by winding on enough turns to fully retract rope, then bend back tangs. It's easier to do than explain - search YouTube for 'Briggs Starter Repair'
phil_saunders(a)bigfoot.com
Phil Saunders
March 2011