Crankshaft pulley fell off...Is my crankshaft still reusable?
After moving some hoses and finally getting to the crank pulley, I found that the previous owner had failed to mention that he had a Evosport pulley installed on the car. My guess is that the pulley was not torqued down correctly when installed but held just enough when driving with the stock belt. Most likely the extra tension from me installing the supercharger made the pulley finally give way, and snapped the woodruff key along with it. My question is that will I have to replace the crankshaft with the minor damage the pulley did to the shaft or could I just removed the broke woodruff key and replace a new one with the OEM crankshaft pulley? I'm really hoping that I won't have to have the motor pulled and replace the entire shaft as this is a very expensive repair job to do. Please let me know if you guys can help or give me some advice. It would be greatly appreciated.
Here are some pictures of the aftermath.


Last edited by pNutz; Nov 30, 2014 at 10:00 PM.




I posted an additional picture of the crankshaft so you can see the other part of the woodruff key.
Polish the crank And you could try putting a new keyway on the crank with the weistec tool for stage 3. Just drill out the crank with their tool and then drill out a stock pulley to match up and install the key way.
Either that or ask Weistec if you could convert over to a 8 rib pulley system and change all the pulleys on the front of the engine to their 8 rib. This would be more $$$ but a better system for sure. The 8 rib system from their stage 3 has two extra keyways you drikk out on the crank so the broken one wouldn't matter. Make sure all pulleys are torqued to spec and blue loctite on all clean threads.
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Polish the crank And you could try putting a new keyway on the crank with the weistec tool for stage 3. Just drill out the crank with their tool and then drill out a stock pulley to match up and install the key way.
Either that or ask Weistec if you could convert over to a 8 rib pulley system and change all the pulleys on the front of the engine to their 8 rib. This would be more $$$ but a better system for sure. The 8 rib system from their stage 3 has two extra keyways you drikk out on the crank so the broken one wouldn't matter. Make sure all pulleys are torqued to spec and blue loctite on all clean threads.
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After moving some hoses and finally getting to the crank pulley, I found that the previous owner had failed to mention that he had a Evosport pulley installed on the car. My guess is that the pulley was not torqued down correctly when installed but held just enough when driving with the stock belt. Most likely the extra tension from me installing the supercharger made the pulley finally give way, and snapped the woodruff key along with it. My question is that will I have to replace the crankshaft with the minor damage the pulley did to the shaft or could I just removed the broke woodruff key and replace a new one with the OEM crankshaft pulley? I'm really hoping that I won't have to have the motor pulled and replace the entire shaft as this is a very expensive repair job to do. Please let me know if you guys can help or give me some advice. It would be greatly appreciated.
Here are some pictures of the aftermath.



The seal replacement shoudl be fairly easy.
When the pulley came off the engine continued to run. Since the seal between the pulley and seal was lost oil came out.
Unless the end of the crankshaft is tapered or the threads are opposite the rotation of the crankshaft the bolt does little to prevent the pulley from spinning on the crankshaft.
My thought is that the woodruff key failed first. This allowed the pulley to spin on the crankshaft. And since the bolt backed out the threads are not in the opposite direction of crankshaft rotation.
When cleaning up the crankshaft be careful not to remove much material. The fit between the pulley and shaft needs to be very close. If when installed (without the bolt) the pulley can be wiggeled around on the cranschaft you will have problems.
Last edited by odonnks; Dec 1, 2014 at 07:21 AM.
Pnutz, ask weistec, I am not sure. Stage 3 pulleys are most likely smaller. I am sure they could machine you a custom one if you ask and explain your situation.
Doesn't look bad
Clean it up
Replace the seal
And see how it runs
I like the 8 grooved pullies
If this means a toothed drive

That being said, if it is threaded reverse of rotation I can't see how the bolt backed out unless the bolt was not in contact with the pulley.
Withe the woodruff key being sheared the bolt should have tightened, most likely to the point of snapping off.
OP. Since you did not install the pulley I recommend also checking to make sure use bolt is not bottoming out before contacting the pulley. If it bottoms out before contacting the pulley it will not properly torque.
That being said, if it is threaded reverse of rotation I can't see how the bolt backed out unless the bolt was not in contact with the pulley.
Withe the woodruff key being sheared the bolt should have tightened, most likely to the point of snapping off.
OP. Since you did not install the pulley I recommend also checking to make sure use bolt is not bottoming out before contacting the pulley. If it bottoms out before contacting the pulley it will not properly torque.
Look at the pics
There is a good one of the bolt
The threads look all bunged up
Which doesn't bode well for the female crank portion
That being said, if it is threaded reverse of rotation I can't see how the bolt backed out unless the bolt was not in contact with the pulley.
Withe the woodruff key being sheared the bolt should have tightened, most likely to the point of snapping off.
OP. Since you did not install the pulley I recommend also checking to make sure use bolt is not bottoming out before contacting the pulley. If it bottoms out before contacting the pulley it will not properly torque.
Cut it into long strips same width as hub
Wrap it around and work it around like sawing/polishing, long smooth strokes (that's what she said lol)
Lightly and regularly checking fit/cleaning with rag
You want the burrs off, not perfect, do NOT remove material, just the burrs
When satisfied clean with brake cleaner and a clean rag, especially threads
Last edited by Ingenieur; Dec 1, 2014 at 01:33 PM.
Last edited by CafeRacer87; Dec 1, 2014 at 02:41 PM.
You will likely pick up a little boost and power once you put a normal size pulley back on since you were under driving the supercharger with the evosport pulley. Good luck with the fix.
The threads look fine after cleaning some gunk and debree off of it. Any ideas on how I can remove the woodruff key without having to removing the timing chain set?
Looks fine
Can you get a better pic of the crank key, perhaps circle it
Make sure you have a strong magnet tool, drop it and you'll be more miserable
Maybe some tape/rags stuffed to prevent it from falling in
Perhaps a pick?
Another set of hands and good lighting would help

Regarding removal of the remaining key, good advice above.
Looking at the pictures I can't tell if the balance key is shared with what I believe is the timing gear inside beyond the seal or if the balancer has its own key.
I'd also consider using a punch to lightly tap it out. The groove should extend to the end of the crank but I can't see that in the pictures. If it does use the punch to tap it perpendicular, away from the crank.


