I have one of these - actually a Glidemaster 340 - the operator control requires a button be pushed in and held down and then the trigger pulled against the handle to get the motor to run.
My trigger control mechanism was not very robust and began to fail - most frustrating. Your mower might have a similar problem.
This is just a guess based on my own experience - there are other reasons why yours doesn't work but if it were mine I would suspect the bizarre operator control.
You might find someone confident enough to take it apart to check it.
Good luck...
June 2015
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