Hi Cheri -
2 answers here:
1 - On the Weedeater, grab the "line release" bump on the spool head and treat it like a child-proof medicine bottle cap. That is, push down slightly while rotating it in either direction until it "unlocks" and then pull everything straight out/up. Additional restringing info is contained on the spool.
2 - PDF files can be easily read by installing the FREE Adobe Acrobat reader. My personal preference is Reader 5.0, an older version (current version is ver. 8.0). Ver. 5.0 loads faster and has been better for the user than all the later versions (Adobe ADDED tons of stuff, thereby bogging down the newer versions.) Here's a comprehensive website for ALL Adobe Reader versions: http://www.oldapps.com/acrobat_reader.htm
BTW, the particular Weedeater unit RTE112C that we own is a piece of crap. The motor speed seems to be too fast: the line keeps breaking! Yes we are using the recommended line diameter.
Good luck with yours.
Russell, June 2008