[Excaliber]

Starter drive staying engaged won't turn the starter, it will 'freewheel' and may damage the starter drive itself. If the starter would engage you would hear it spinning, even if the drive itself does not engage the flywheel.

How's the ground from the starter back to the battery? Typical would be, starter grounds to engine, engine grounds to negative on battery terminal. My negative terminal is attached directly at a bell housing bolt.