http://www.blackanddecker.com/Default.aspx
You will need to go to this site, click on parts and sign up for servicenet.com, then sign in with the model number (cst 1000) and it will bring up the model. Then click on that link and you can see a detailed schematic along with part numbers (the whole thing is printable).
Mark L. Baker
January 2006
Automatic Answer
While you wait for answers, we may have found some information which could help you.
howtomendit.com for free repair help, information and advice.
Try fixfault.com to fix grass trimmers.