GM Forum - Buick, Cadillac, Olds, GMC & Pontiac chat - Bonneville SSEi (1992) harmonic balancer broken, bolt broken.

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Bonneville SSEi (1992) harmonic balancer broken, bolt broken.

Hello guys,

I´m from germany and just bought my own Pontiac Bonneville SSEi :-)
It´s really a nice car but it does have a really big problem: The harmonic balancer broke and caused some damage on the crankshaft....

That means, the crankshaft is ok and I have a new crankshaft pulley/harmonic balancer here and wanted to replace the old one...but now they told me that the bolt (which connect the balancer with the crankshaft) is gone because the broken harmonic balancer or the pulley shaped the bolt :-(

I´m 19 and don´t have the 3.000 $ to remove the old crankshaft and replace it with a new one (a new crankshaft can be bought for 200 $)! But they have to open the complete engine...

I did hear some noises coming from the pulley and then my car lost the acceleration, now I know why.

What can I do to attach the new pulley with the crankshaft?
I heard there are "Woodruff keys" that can solve this problem.
This isn´t my first american car but the first that really have problems and a broken harmonic balancer and no way to connect the new crankshaft pulley is a huge problem.
I owned the car for 3 weeks and now it´s damaged, thats so ****** up :-(

Thanks for your help or advice in advance
best regards from Germany
Nils Wilhelm

It really depends upon how much damage the balancer did to the shaft itself. It still may be usable. Are you able to get it off and take pictures of the shaft? You are correct about the woodruff key. It could have just sheared off and just spun.

Post up some pictures. If the damage isn't to bad you may be able to clean it up and put in the new HB. You just need to get the old broken bolt out.

Thanks for your comments, I will try to get some pics.
During my conversation with summitracing.com I know that this "bolt" is called crank key, this little piece is gone now because of the broken pulley.

I really hope the crankshaft is ok :-(

Is there a chance to look at the crankshaft without opening the engine?
I guess some parts from the pulley flew into the crankshaft, of course I need to clean it up.

Thanks :)

I will upload the pictures tomorrow...GM says I have to replace the crankshaft, I hope not :(
The car lost it´s acceleration in 1 week, not more than ca. 3.000 rpm (full boost) and at least I had to push the gas pedal really hard that the engine could start and run.
Could the engine be broken now?

OK, the HB is gone. Can you get a picture of the key way on the crankshaft? I didn't see it. You may be OK as long as the shaft is not all gouged up.

If you can get the broken key out and clean up the shaft, I see no reason to replace the crankshaft.

That sounds good but isn´t it dangerous with such a small piece on the crankshaft? GM/Opel said the new HB/pulley will not hold for a long time on the crankshaft...why are they telling me this? They wanted me to spend 3.000 $ for a full crankshaft-replacement :confused::nm

But I will follow your tips...:)

Can I use this woodruff keys here?