While you wait for answers, we may have found some information which could help you.
Click here for Decker Working GoingBlack & Decker GL540 trimmer nylon cord unravelling how can I fix that?
Drive belt?
how to rewind the spool on black & decker strimmer gl720?
Black and Decker GL565C?
Black & Decker GW250 leaf blower/vacuum Diagram?
How easy is it to replace a pull chord on a black and decker petrol strimm?