I would have to agree with the first guys about the Pulley seperating. It happened to me, and what a life it created. My story was like yours, except the outer part of pulley fell off completely, popped a whole in my transmision pan, and etc. Anyway, you can buy the tool at the fowllowing link for $40.

http://www.ipdusa.com/ProductsCat.aspx?CategoryID=622&NodeID=1419&RootID=629

while you're removing the pulley, you may as well replace your timing belt kit (if needed), and all new belts. this can cost no more than $150 for tools, and parts, but you won't regret, I went thru it all from this pulley (balancer) problem.

The crankshaft removal tool, does the job with you in less than 2 minutes. Other ways can be really time consuming. Trust me, I've tried, and it hurts.

OH yeah, if you do change the timing belt, there is one more seal that can be replaced, once you open the timing bel cover, I can't remmber the name of it.

1990 740GL Rex, 200K, plan to keep it double the miles, that's another reason I bought the removal tool.