Here's some Places to look
www.drystacked.com/Walbro Carburetor Theory ebook1.pdf
http://www.m-and-d.com/Walbro_carburetor_parts.html
http://www.m-and-d.com/zama_carburetor.html
Best Parts lookup I've found for all Lawn Equipment.
http://wssemw.arinet.com/scripts/EmpartISAPI.dll?MF
Mike E
September 2008