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Old 10-14-2020, 01:45 PM   #1
Starwood
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Balancer Wobble Question

So...after my first couple of starts with the new 350 Crate swap, I noticed a VERY slight wobble on the crankshaft. I understand even the slightest wobble can cause big time problems.

Thinking it might the pulley, I took that off and gave a quick look to just the balancer in motion and sure enough - slight wobble remains. I used the right tools and was very careful, but I guess I didn't seat it perfectly.

My question is: Can a new Balancer be pulled and reset without doing any damage to it - or is it best to just pull and install a new one?

They're only $80, but I'm going way over budget on this swap.

Thanks in advance for any replies.
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Old 10-14-2020, 02:00 PM   #2
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Re: Balancer Wobble Question

Quick follow up: I know I can just try to reset the existing balancer, and give it another look but I am more curious if any damage might have been done to the balancer with it running before I noticed the wobble.

Sorry if I wasn't clear and thanks again for any replies.
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Old 10-14-2020, 03:45 PM   #3
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Re: Balancer Wobble Question

Balancer install is a no brainer. They slide on with a little help.

Something that really concerns me is your statement ‘after the first couple of starts’.
You did break that cam in correctly, right.
That means 2000 rpm for 20 minutes minimum.
If you just fired it up and no break in you could have wiped a lobe or two on the cam.
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Old 10-14-2020, 08:33 PM   #4
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Re: Balancer Wobble Question

If you struck the metal ring outside the elastomeric ring, you could have knocked it out of line. If you put it on with a hammer, for example. I wouldn't even bother to try straightening it out, the damage is done. I'm going to say, though that I'd personally pull the balancer and check the radial runout on the crankshaft before I did anything else. "New" doesn't always mean "good". The crank could be bent. Those things happen. I've seen it in my mechanic days. Nothing like putting a rebuilt engine in, only to have to take it out and sent it back to the rebuilder.
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Old 10-15-2020, 07:26 AM   #5
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Re: Balancer Wobble Question

I pulled it and reset the HB and the wobble remains.
Dublin GM is going to replace no problem.

If it the new one wobbles...then it's the crank.
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Old 10-15-2020, 09:03 AM   #6
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Re: Balancer Wobble Question

Did you see my question about whether you broke in the cam or not?
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Old 10-15-2020, 09:58 AM   #7
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Re: Balancer Wobble Question

Quote:
Originally Posted by geezer#99 View Post
Did you see my question about whether you broke in the cam or not?
I've seen my fair share of wiped cam lobes from improper break in (more so years ago) and I've never seen a harmonic balancer wobble because of a wiped cam lobe. Wondering how a wiped cam lobe would affect the crank? Besides symptoms with how it runs, the only visible clue of a wipe cam lobe is the valve train on that cylinder not opening / closing fully.
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Old 10-15-2020, 10:06 AM   #8
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Re: Balancer Wobble Question

I don't want to speak for Geezer, but I think he is asking because of the first sentence you typed, "So...after my first couple of starts with the new 350 Crate swap..." I believe that is why he is referring to the cam lobe(s).
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Old 10-15-2020, 11:03 AM   #9
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Re: Balancer Wobble Question

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Originally Posted by Rickysnickers View Post
I don't want to speak for Geezer, but I think he is asking because of the first sentence you typed, "So...after my first couple of starts with the new 350 Crate swap..." I believe that is why he is referring to the cam lobe(s).
You are correct!
Within a short span of time (less than 24 hours) he went from having trouble Finding tdc to get it ready to start to actually starting it and letting it idle.
Not much time in there for cam break in. Wobbly balancer or not.
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