I got a 2003 300ex that won’t start. Starter spins but engine will not turn over. Assumed it was the key way or starter clutch. Pulled the flywheel off key way is grabbing the flywheel and starter clutch works as it should. The crankshaft turns either direction with ease by hand. Someone help me out here. Broken rod? Broken or stretched Timing chain? Stripped crank gear?