sound like your engine mount screws were loose! When it was loose, the engine will shift towards the main shaft when you try to pull the starter. That shift will cause a gap problem between the main bell gear (the one that attached to the motor) and the main gear on the center shaft. That reduction in gap will make the engine brake (more like not moving anywhere). What you can do is loosen the engine mount screws (not too loose...just enough that you can move the engine from side to side), take a piece of paper and slip it in between the bell gear and the center shaft gear. Slide the bell so it would slightly squeeze the paper in between the main gear on center shaft. Tightened the engine mount screws. Restart your car and see the difference.
HOpe that helps
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