The first thing to check for is that the drive belt is not broken. Sometimes they'll snap, but stay attached hanging to the flywheels, so you won't see them in the yard. Of course, if this model is shaft-drive, disregard the above advice. That's about all I can tell you, but my guess is a broken drive belt. If the drive belt's OK, I have no idea what your problem is.
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The first thing to check for is that the drive belt is not broken. Sometimes they'll snap, but stay attached hanging to the flywheels, so you won't see them in the yard. Of course, if this model is shaft-drive, disregard the above advice. That's about all I can tell you, but my guess is a broken drive belt. If the drive belt's OK, I have no idea what your problem is.