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Discussion Starter #1
After a rigorous checkout run on my Stepnose 3.0 12V motor, I discovered my Water Pump / A/C belt was shredded and my alternator belt missing. Also the V-Belt groove in the crank pulley had a piece out of it, leaving a 1 inch long hole at the base of the groove. The alternator and A/C brackets are custom, but they're all solidly in place. The failure scenario is anyone's guess, but I'm open to ideas.

Anyway, does anyone have a crankshaft pulley they can spare?

Thanks
 

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Belt alignment issue maybe, or you have a badly failed bearing that permitted slack? But that broken pulley will need replacement ... is that the cause? Did a stone go through it?

Pete
 

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I'm betting a rock.
 

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Whatever force broke the pulley was exerted by the v belt which then broke taking out the serpentine belt on its way out of the engine compartment.
 

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Discussion Starter #6
Thanks Guys:

I think the opinion is the v-belt went first and that took out the serpentine. Has anyone seen a crank pulley fail like this? Is it possible that the pulley failed first and that caused the V-belt to go?

Does anyone know where I can get a pulley?

Thanks again
 

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After a rigorous checkout run on my Stepnose 3.0 12V motor, I discovered my Water Pump / A/C belt was shredded and my alternator belt missing. Also the V-Belt groove in the crank pulley had a piece out of it, leaving a 1 inch long hole at the base of the groove. The alternator and A/C brackets are custom, but they're all solidly in place. The failure scenario is anyone's guess, but I'm open to ideas.

Anyway, does anyone have a crankshaft pulley they can spare?

Thanks
I think the most concerning part of all of this is the chunk taken out of the crank pulley. I have one if you need it.

I sit here and think, how does a rubber belt rip out a chunk of metal? I just wonder if it was already cracked and not seen? I think about the Key on the end of the shaft under that area that holds the crank pulley in place. Could that have done something? Not sure if it could, maybe it was loose? No idea. Too much tension on belt thus creating lots of heat to create a crack?

I think the piece that broke off, ripped the belt and thus tearing into the other belt and shredding it.
 

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I think a rock got caught between the belt and the pulley, tearing the belt due to excess tension as the belt goes over the rock, and that force pushed the rock into the pulley, breaking out a chunk.

You could run the car with that chunk out of the pulley, but not for a real long time. I doubt that chunk being out would damage the belt quickly, perhaps even if at all. Certainly Ok for a 'get home' solution, IMO.

The big deal is that the pulley is now out of balance. That might limit just how long you would want to run the engine in this condition, for either the long term fatigue life of the unbalanced pulley, and any potential long term excessive wear to crank bearing or seal.
 
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