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 1,000 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!
  1. Home
  2. Questions
  3. 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: emergency brake broke

If the cable has broken, to obtain a repair quote, please click on "Get a Quote" at YourMechanic's emergency brake cable replacement service page. As long as the parking break lever is not damaged and the remainder of the cable...

Q: Knocking sound when the car is moving, but not accelerating or braking.

Hi there. Check the lug nuts on the front wheels and make sure that they are tight. The wheel could be loose and moving around. If the lug nuts are tight, then check around the wheel and see if there...

Q: I need to replace the harmonic balancer on my 94 buick. Is it ok to drive to go pick up the parts?

If the harmonic balancer is known to be defective, the only prudent course is to not operate the engine until the balancer is replaced. There are at least two risks: 1) the balancer could completely separate causing further damage; and...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
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...