The first question is whether the chain clutch is disengaging, Paul. If one of the springs in the centrifugal clutch is broken, you'd get about what you've got. Usually you can't pull it fast enough to start, and it won't idle anyway, if the clutch is locked in the engaged position. Also, if the bar nose sprocket is seized, it may have burned up the clutch so it stays locked in, with the same result.
