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Harmonic Balancer/Crankshaft pulley wobble?

Hey everyone!

Is the crankshaft pulley and harmonic balancer the same thing? I was looking at my drive belt and pulleys with the engine running yesterday and noticed the crankshaft pulley/harmonic balancer wobbling.

Should I be worried or a little wobble is normal?

I’ve had to replace several on my GMs. The balancer is packed with rubber that comes loose over time and causes a wobble. On one of mine it sheared the crank sensor and the car was dead. On another pretty new Buick it caused a leak from the front seal. So yeah, a wobble is not normal and the balancer needs to be replaced. Last time it cost me close to $500.


I never knew this part could go bad. Never heard anyone replacing a balancer before either.

Can a DIYer replace it? I know you need a pulley kit to take it off and put it back. What I mean is taking the bolt out of it without an impact, just using a breaker bar.

I already ordered a balancer. I had lots of reward points that I didn’t use from Autozone, phew!

If you don’t have an impact, you could remove the starter and use a large screwdriver or piece of hard wood as a wedge to block the flywheel/ring gear from moving. Then use a breaker bar on on the crankshaft bolt.

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Okay, I think I can try that.

I got a question though, what do you think about the method of wedging the breaker bar against a solid metal part somewhere and using the starter to loosen the bolt? This way, I don’t have to remove anything.

I read this is a method some mechanics use but I have also seen people going against this method.

I can try renting a place where I can use an impact but I am trying to save some money.

Triathlor: You mean like the fellow in this video?

Go to the 2 minute mark to see it.

Not sure I would try this. With my luck, the wrench handle would go flying all over the place :worried:

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You could try using the starter to loosen the bolt, though I never liked that approach.
The problem is the starter won’t help you when you need to tighten the bolt.

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Yep exactly this.

Hum you are right. :roll_eyes:

What about a strap wrench?

You could try it. Some of the techniques in the video will likely work as well. It all depends on the torque value you need for the crank bolt.

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I’ve only pulled one off once when my timing chain went. I tried various ways to hold the thing like an improvised strap but nothing worked because the timing chain was off. I had to pull the pan anyway so I ended up wedging a block on the crank to hold it while I got the bolt off. I don’t think I would have had a problem with the timing chain intact but that was a GM.

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I removed the crank pulley on my Corolla to change the timing belt using a diyer method which might apply in your case. To hold it still while I removed the crank bolt, I noticed there were two small holes 180 degrees apart on the face of the pulley. I made myself a sturdy wooden stick using plywood with two wood screws through it, that matched the spacing of the holes. Then I wedged that stick against the ground in an orientation to prevent the pulley from rotating. Crank bolt removed easy-peasy with a socket & breaker bar. There’s a tool called a “pin tool” you can buy that does that same thing. But my wooden stick home-made method worked fine for me.

One thing to be careful about, when pulling the pulley from the crankshaft using a puller, first install the bolt back in-- but not tight – then use the head of the bolt to push on with the center of the puller. What you have to be careful about, remember to monitor the pulley while doing this, so that it doesn’t meet up with the head of the bolt. If that happens and you continue to pull on it with the puller something expensive will break.

I’ve seen ideas in magazines where a diy’er – to remove the bolt – will remove the starter motor and wedge something against the flywheel teeth to hold the crankshaft steady also. Seems like that would work, but removing the starter motor is a pretty big job sometimes. (Just noticed this idea already posted above, sorry for the repeat.)

For a quick tutorial on how the harmonic balancer works and ways it can fail, click below.

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Thanks for the tip George. :sunglasses: Is this the tool you are referring to?

Apparently, removing to the starter motor is not as difficult as I thought. You can access it from above in a Mazda 6. That’s the flywheel ring gear exposed in the image below.

I have lots of wood here that I can use for this. I can try your method. Thanks!

Yes, that’s one version. For that tool to work the two holes it grabs obviously have to be present. Does your crank pulley sport those two holes? If so, that’s a good method for a diy’er.

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Hum, mine looks like this.:thinking: S

Nothing like I’ve seen but if it wobbles, something is wrong-hope the crank isn’t bent. At any rate if it’s the six, Rockauto has a repair bushing for about $6, compared to $44 for the pulley. For some reason the one for the 4 is $170. That’s the extent of what I know. Maybe a mechanic can shed some light on it.

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Thanks Bing. I am curious, what can damage a crankshaft?