check out what happened to me yesterday at work while trying to replace my front engine seal. turns out that little key on the crank snout was loose and ****ed up the balancer as i was putting it back in. after the old balancer was in i noticed the seal didnt go in straight so i took it back out then noticed the damage it did. luckily i was able to get a new balancer and filed the key so it slid easily on the balancer groove. what would cause the key to come loose? will this eventually cause bigger problems? i had to put some wheel bearing grease on the key so it stayed in there and didnt drop, then slowly pushed the new balancer in. luckily i was able to finish the job and drive the car again.

also i ran the car for about 2 minutes after putting the new one in, then decided to change the oil since there was a big chunk of metal missing from the balancer. should i not worry about any metal anymore or should i try to change the oil again? (it doesnt cost me anything).

here's a pic of the balancer and the installing tool i used which i bought several months ago and came in real handy yesterday.