On my cheap electric chain saw there's an adjusting wheel to move the blade backwards and forward. To get it to move easily I need to relax the tension screw that holds the cutting blade tight against the machine's body.
Yours may be different - but probably not that much different.
I discover that the cutting blade that carries the chain may also be taken off and put on the other way up to even out the wear.
I found this PDF useful...
http://www.stihllibrary.com/pdf/SharpAdvice061301final.pdf
Take care...
Peccavi
March 2011
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