This machine uses a two stroke petrol/oil mixture, the mixture is 40/1 using proper two stroke oil. If you have not used a two stroke mix then I think it may be seriously damaged and going for a trip to the big lawn in the sky, sorry.
Mickey
May 2011
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.