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Q: My aftermarket crankshaft pulley is wobbling a little when it idles. Does it just need to be tightened, or replaced?

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Really concerned here. Heard a weird noise coming from my engine. Looked under the hood with my friend and saw my harmonic balancer/crankshaft pulley wobbling a little at an idle. It doesn't shake or wobble after I rev up the engine though. I have the aluminum aftermarket 3sx pulley on there so I don't know why it's doing that. It was also professionally installed. Is there a way to just tighten it or should I replace the pulley all together? I have a used one off of a parts car that I know for a fact works, but obviously if I don't have to remove it I don't want to. I'd just rather keep the one that's on there in case all I have to do is tighten it. I have the automatic transmission by the way. Thanks.

My car has 200000 miles.
My car has an automatic transmission.

The harmonic balancer should not wobble at all. The heavy bolt that holds the balancer to the crankshaft snout is quite tight. Presumably the balancer bolt was torqued to the Factory Service Manual value, and so you cannot safely tighten it any further and even if you did it wouldn’t make any difference because the balancer is fixed in position against a shoulder on the snout. You could check to make sure the bolt was actually tightened though to the torque specification. If the bolt was tightened, the crankshaft snout is not bent, and yet the balancer wobbles, the balancer is defective. If you desire that the balancer be examined to determine if it is defective, and replace it if required, please request harmonic balancer diagnostic/replacement and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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