Skip the auto shop - Our mechanics make house calls

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

asked by on

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.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  • Home
  • Questions
  • My aftermarket crankshaft pulley is wobbling a little when it idles. Does it just need to be tightened, or replaced?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Clutch not working properly.

This sounds like you have a busted clutch or transmission along with your axles being broken. The broken axles may be an indication that the transmission input shaft or clutch is broken. The engine oil cooler would have to be...

Q: Shifting problem? 1998 Mercury Villager

Hi There, This may be related to a faulty transmission control solenoid. since automatic transmissions use pressurized hydraulic fluid to change gears, every time a gear change is required, the car's computer activates a transmission solenoid, which directs transmission fluid...

Q: Harmonic balancer broke replaced now won't start

There are two main possibilities. Depending on how or why the balancer failed (e.g., did it fail suddenly accompanied by the car engine completely stopping), it is possible the timing belt has slipped or is even broken. It is also...

Related articles

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.