Sounds like the outer part of your crank pulley is really loose and very wobbley. Probably also the cause of your charging problems. The pulley is not too hard to remove. Just the right socket (22mm?) and a BIG BREAKER BAR. The trick is to stop the engine from turning while you're removing the nut. I've read about the success of the "rope trick" although I haven't personally tried it. I believe you remove a spark plug and insert a few inches of one end of some thick nylon rope into the combustion chamber. Turn the engine manually untill the piston compresses the rope against the cylinderhead and stops the rotation. After the nut is removed and the pulley replaced turn the engine back the other way until its stopped again and tighten the nut. Rotate backwards again a little and pull the rope out. Loosening the other spark plugs a little makes it easier to turn the engine.