I decided to drive the Vette to work today. As I was pulling into the parking lot, my power steering went out and I heard a thumping sound - I figured the serpentine belt had broken. I parked the car and popped the hood - the belt had come loose, but was OK. I started looking at the pulleys and all of them were in line except for the harmonic balancer - it was jutting out about 1/4". I figured the bolt had slipped or something and I'd just fix it after work.

Well, after work I had planned on tightening up the bolt or just banging the balancer back into place with a hammer. However, when I put my hand on the balancer it just fell off.

Here are pics of it and the bolt:
http://langhoff.dhs.org/balancer.jpg
http://langhoff.dhs.org/strippedbolt.jpg

As you can tell, the bolt was stripped pretty badly. The bigger concern, however, is the inside of the balancer - it's rounded out completely. It slips right on and off the crank without any resistance. The crank itself has some scrapes on it from where the notched edge of the balancer rubbed against it.

Any ideas on what could have caused this? Do you think I could get away with just using another balancer and helicoiling the crank bolt hole? Or does the crank probably need replacing?

Thanks for any input.

 

You are luck if you did not hurt your motor. I had a balancer fly off under a load. Balancer flew off and crank shaft broke in half. Was not a pretty sight . Balancer flew out of the engine compartment ontp the road and into and out off a ditch. Found it a good 20 feet off of the road.

 

Pictures arent working...but anyways....

Helicoil is pretty much your only option, which involves removing the crank anyways (unless you plan on tapping as it sits...eeeek)

I actually broke my bolt off in the crank pulling the hub on. Used red locktight and the hub has stayed firmly on ever since...crossing fingers.